Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 25/12/2017. Sandringham , United Kingdom. HM Queen Elizabeth II Christmas Day Church Service. The Duke and the Duchess of Cambridge and Meghan Markle, Prince Harry curtsy to the Queen as they join HM Queen Elizabeth II at St. Mary Magdalene Church on her Sandringham estate in Norfolk, after the Christmas Day service. Picture by Andrew Parsons / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 25/12/2017. Sandringham , United Kingdom. HM Queen Elizabeth II Christmas Day Church Service. Catherine, Duchess of Cambridge with Prince William, The Duke of Cambridge, Prince Harry and Meghan walking to join HM Queen Elizabeth II at St. Mary Magdalene Church on her Sandringham estate in Norfolk, for the Christmas Day service. Picture by Andrew Parsons / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 25/12/2017. Sandringham , United Kingdom. HM Queen Elizabeth II Christmas Day Church Service. Catherine, The Duchess of Cambridge laughing with Meghan Markle as they join HM Queen Elizabeth II at St. Mary Magdalene Church on her Sandringham estate in Norfolk, for the Christmas Day service. Picture by Andrew Parsons / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 25/12/2017. Sandringham , United Kingdom. HM Queen Elizabeth II Christmas Day Church Service. Catherine, Duchess of Cambridge with Prince William, The Duke of Cambridge, Prince Harry and Meghan walking to join HM Queen Elizabeth II at St. Mary Magdalene Church on her Sandringham estate in Norfolk, for the Christmas Day service. Picture by Andrew Parsons / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 25/12/2017. Sandringham , United Kingdom. HM Queen Elizabeth II Christmas Day Church Service. Prince Harry and Meghan Meghan Markle with the Duke of Edinburgh join HM Queen Elizabeth II at St. Mary Magdalene Church on her Sandringham estate in Norfolk, for the Christmas Day service. Picture by Andrew Parsons / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 25/12/2017. Sandringham , United Kingdom. HM Queen Elizabeth II Christmas Day Church Service. Prince Harry and Meghan Meghan Markle with the Duchess of Cambridge join HM Queen Elizabeth II at St. Mary Magdalene Church on her Sandringham estate t in Norfolk, for the Christmas Day service. Picture by Andrew Parsons / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 25/12/2017. Sandringham , United Kingdom. HM Queen Elizabeth II Christmas Day Church Service. Prince Harry and Meghan Meghan Markle with the Duke of Edinburgh join HM Queen Elizabeth II at St. Mary Magdalene Church on her Sandringham estate in Norfolk, for the Christmas Day service. Picture by Andrew Parsons / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 25/12/2017. Sandringham , United Kingdom. HM Queen Elizabeth II Christmas Day Church Service. Prince Harry and Meghan Markle with the Duke and Duchess of Cambridge join HM Queen Elizabeth II at St. Mary Magdalene Church on her Sandringham estate t in Norfolk, for the Christmas Day service. Picture by Andrew Parsons / Parsons Media / eyevine

21/12/2017. Kings Lynn , United Kingdom. The Queen and the Duke of Edinburgh arriving at Kings Lynn train station in Norfolk, United Kingdom, for the start of their traditional Christmas holiday at Sandringham. for Christmas holidays. Picture by Stephen Lock / i-Images / eyevine

21/12/2017. Kings Lynn , United Kingdom. The Queen arriving at Kings Lynn train station in Norfolk, United Kingdom, for the start of her traditional Christmas holiday at Sandringham. Picture by Stephen Lock / i-Images / eyevine

21/12/2017. Kings Lynn , United Kingdom. The Queen arriving at Kings Lynn train station in Norfolk, United Kingdom, for the start of her traditional Christmas holiday at Sandringham. Picture by Stephen Lock / i-Images / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 12/11/2017. London, United Kingdom. HM The Queen Elizabeth II- Remembrance Sunday. HM The Queen Elizabeth II joined by The Duke of Edinburgh, Prince Charles, The Duchess of Cornwall, The Duke and Duchess of Cambridge and Prince Harry attend Remembrance Sunday at the Cenotaph, London. Picture by Andrew Parsons / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 12/11/2017. London, United Kingdom. HM The Queen Elizabeth II- Remembrance Sunday. HM The Queen Elizabeth II joined by The Duke of Edinburgh, Prince Charles, The Duchess of Cornwall, The Duke and Duchess of Cambridge and Prince Harry attend Remembrance Sunday at the Cenotaph, London. Picture by Andrew Parsons / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 12/11/2017. London, United Kingdom. HM The Queen Elizabeth II- Remembrance Sunday. HM The Queen Elizabeth II joined by The Duke of Edinburgh, Prince Charles, The Duchess of Cornwall, The Duke and Duchess of Cambridge and Prince Harry attend Remembrance Sunday at the Cenotaph, London. Picture by Andrew Parsons / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 12/11/2017. London, United Kingdom. HM The Queen Elizabeth II- Remembrance Sunday. HM The Queen Elizabeth II joined by The Duke of Edinburgh, Prince Charles, The Duchess of Cornwall, The Duke and Duchess of Cambridge and Prince Harry attend Remembrance Sunday at the Cenotaph, London. Picture by Andrew Parsons / Parsons Media / eyevine

12/11/2017. London, United Kingdom. Remembrance Sunday. HM The Queen, HRH The Duke of Edinburgh and HRH The Duchess of Cornwall attend the Remembrance Sunday service at the Cenotaph. Picture by i-Images / eyevine

12/11/2017. London, United Kingdom. Remembrance Sunday. HM The Queen Elizabeth II and the Duke of Edinburgh attend the Remembrance Sunday service at the Cenotaph. Picture by i-Images / eyevine

12/11/2017. London, United Kingdom. HM The Queen Elizabeth II- Remembrance Sunday. HM The Queen Elizabeth II joined by The Duke of Edinburgh, Prince Charles, The Duchess of Cornwall, The Duke and Duchess of Cambridge and Prince Harry attend Remembrance Sunday at the Cenotaph, London. Picture by Andrew Parsons / i-Images / eyevine

12/11/2017. London, United Kingdom. HM The Queen Elizabeth II- Remembrance Sunday. HM The Queen Elizabeth II joined by The Duke of Edinburgh, Prince Charles, The Duchess of Cornwall, The Duke and Duchess of Cambridge and Prince Harry attend Remembrance Sunday at the Cenotaph, London. Picture by Andrew Parsons / i-Images / eyevine

12/11/2017. London, United Kingdom. HM The Queen Elizabeth II- Remembrance Sunday. HM The Queen Elizabeth II joined by The Duke of Edinburgh, Prince Charles, The Duchess of Cornwall, The Duke and Duchess of Cambridge and Prince Harry attend Remembrance Sunday at the Cenotaph, London. Picture by Andrew Parsons / i-Images / eyevine

04/09/2017. North Queensferry , United Kingdom. The Duke of Edinburgh at the opening of the Queensferry Crossing which spans the Firth of Forth in Scotland, United Kingdom. Picture by Stephen Lock / i-Images / eyevine

04/09/2017. North Queensferry , United Kingdom. The Queen and Duke of Edinburgh at the opening of the Queensferry Crossing which spans the Firth of Forth in Scotland, United Kingdom. Picture by Stephen Lock / i-Images / eyevine

02/09/2017. Braemar,Scotland, United Kingdom. The Queen and Duke of Edinburgh watch the Braemar Gathering in Scotland. Picture by Stephen Lock / i-Images / eyevine

02/09/2017. Braemar,Scotland, United Kingdom. The Duke of Edinburgh arriving at the Braemar Gathering in Scotland. Picture by Stephen Lock / i-Images / eyevine

02/09/2017. Braemar ,Scotland, United Kingdom. The Queen, Duke of Edinburgh, Prince of Wales and Princess Royal at the Braemar Gathering in Scotland. Picture by Stephen Lock / i-Images / eyevine

02/09/2017. Braemar,Scotland, United Kingdom. The Queen and Duke of Edinburgh watch the Braemar Gathering in Scotland. Picture by Stephen Lock / i-Images / eyevine

02/08/2017. London, United Kingdom. The Duke of Edinburgh at his last official engagement before he retires as he attends the Captain General's Parade at Buckingham Palace in London. Picture by CPNA / i-Images / eyevine

02/08/2017. London, United Kingdom. The Duke of Edinburgh attending the Captain General's Parade. The Duke of Edinburgh attends The Captain General's Parade on the Buckingham Palace Forecourt in London on Wednesday 2nd August 2017. The Captain General's Parade is The Dukes final individual Royal Engagement although he may choose to attend certain events, alongside The Queen, from time to time. The parade marked the finale of the Royal Marines 1664 Global Challenge which saw Royal Marines from around the country running 16.64 miles each day for 100 days, totalling a distance of 1664 miles. Picture by i-Images / Pool / eyevine

02/08/2017. London, United Kingdom. The Duke of Edinburgh attending the Captain General's Parade. The Duke of Edinburgh attends The Captain General's Parade on the Buckingham Palace Forecourt in London on Wednesday 2nd August 2017. The Captain General's Parade is The Dukes final individual Royal Engagement although he may choose to attend certain events, alongside The Queen, from time to time. The parade marked the finale of the Royal Marines 1664 Global Challenge which saw Royal Marines from around the country running 16.64 miles each day for 100 days, totalling a distance of 1664 miles. Picture by i-Images / Pool / eyevine

02/08/2017. London, United Kingdom. The Duke of Edinburgh attending the Captain General's Parade. The Duke of Edinburgh attends The Captain General's Parade on the Buckingham Palace Forecourt in London on Wednesday 2nd August 2017. The Captain General's Parade is The Dukes final individual Royal Engagement although he may choose to attend certain events, alongside The Queen, from time to time. The parade marked the finale of the Royal Marines 1664 Global Challenge which saw Royal Marines from around the country running 16.64 miles each day for 100 days, totalling a distance of 1664 miles. Picture by i-Images / Pool / eyevine

02/08/2017. London, United Kingdom. The Duke of Edinburgh attending the Captain General's Parade. The Duke of Edinburgh attends The Captain General's Parade on the Buckingham Palace Forecourt in London on Wednesday 2nd August 2017. The Captain General's Parade is The Dukes final individual Royal Engagement although he may choose to attend certain events, alongside The Queen, from time to time. The parade marked the finale of the Royal Marines 1664 Global Challenge which saw Royal Marines from around the country running 16.64 miles each day for 100 days, totalling a distance of 1664 miles. Picture by i-Images / Pool / eyevine

02/08/2017. London, United Kingdom. The Duke of Edinburgh attending the Captain General's Parade. The Duke of Edinburgh attending the Captain General's Parade as his final individual public engagement, at Buckingham Palace in London. The Duke meets Royal Marines who have completed a mammoth 1,664 mile trek on Wednesday - his final official royal event before he retires from public engagements. Picture by i-Images / Pool / eyevine

02/08/2017. London, United Kingdom. The Duke of Edinburgh attending the Captain General's Parade. The Duke of Edinburgh attends The Captain General's Parade on the Buckingham Palace Forecourt in London on Wednesday 2nd August 2017. The Captain General's Parade is The Dukes final individual Royal Engagement although he may choose to attend certain events, alongside The Queen, from time to time. The parade marked the finale of the Royal Marines 1664 Global Challenge which saw Royal Marines from around the country running 16.64 miles each day for 100 days, totalling a distance of 1664 miles. Picture by i-Images / Pool / eyevine

02/08/2017. London, United Kingdom. The Duke of Edinburgh attending the Captain General's Parade. The Duke of Edinburgh attends The Captain General's Parade on the Buckingham Palace Forecourt in London on Wednesday 2nd August 2017. The Captain General's Parade is The Dukes final individual Royal Engagement although he may choose to attend certain events, alongside The Queen, from time to time. The parade marked the finale of the Royal Marines 1664 Global Challenge which saw Royal Marines from around the country running 16.64 miles each day for 100 days, totalling a distance of 1664 miles. Picture by i-Images / Pool / eyevine

02/08/2017. London, United Kingdom. The Duke of Edinburgh attending the Captain General's Parade. The Duke of Edinburgh attends The Captain General's Parade on the Buckingham Palace Forecourt in London on Wednesday 2nd August 2017. The Captain General's Parade is The Dukes final individual Royal Engagement although he may choose to attend certain events, alongside The Queen, from time to time. The parade marked the finale of the Royal Marines 1664 Global Challenge which saw Royal Marines from around the country running 16.64 miles each day for 100 days, totalling a distance of 1664 miles. Picture by i-Images / Pool / eyevine

02/08/2017. London, United Kingdom. The Duke of Edinburgh attending the Captain General's Parade. The Duke of Edinburgh attending the Captain General's Parade as his final individual public engagement, at Buckingham Palace in London. The Duke meets Royal Marines who have completed a mammoth 1,664 mile trek on Wednesday - his final official royal event before he retires from public engagements. Picture by i-Images / Pool / eyevine

02/08/2017. London, United Kingdom. The Duke of Edinburgh attending the Captain General's Parade. The Duke of Edinburgh attending the Captain General's Parade as his final individual public engagement, at Buckingham Palace in London. The Duke meets Royal Marines who have completed a mammoth 1,664 mile trek on Wednesday - his final official royal event before he retires from public engagements. Picture by i-Images / Pool / eyevine

02/08/2017. London, United Kingdom. The Duke of Edinburgh attending the Captain General's Parade. The Duke of Edinburgh attending the Captain General's Parade as his final individual public engagement, at Buckingham Palace in London. The Duke meets Royal Marines who have completed a mammoth 1,664 mile trek on Wednesday - his final official royal event before he retires from public engagements. Picture by i-Images / Pool / eyevine

02/08/2017. London, United Kingdom. The Duke of Edinburgh attending the Captain General's Parade. The Duke of Edinburgh attending the Captain General's Parade as his final individual public engagement, at Buckingham Palace in London. The Duke meets Royal Marines who have completed a mammoth 1,664 mile trek on Wednesday - his final official royal event before he retires from public engagements. Picture by i-Images / Pool / eyevine

02/08/2017. London, United Kingdom. The Duke of Edinburgh attending the Captain General's Parade. The Duke of Edinburgh attends The Captain General's Parade on the Buckingham Palace Forecourt in London on Wednesday 2nd August 2017. The Captain General's Parade is The Dukes final individual Royal Engagement although he may choose to attend certain events, alongside The Queen, from time to time. The parade marked the finale of the Royal Marines 1664 Global Challenge which saw Royal Marines from around the country running 16.64 miles each day for 100 days, totalling a distance of 1664 miles. Picture by i-Images / Pool / eyevine

02/08/2017. London, United Kingdom. The Duke of Edinburgh attending the Captain General's Parade. The Duke of Edinburgh attending the Captain General's Parade as his final individual public engagement, at Buckingham Palace in London. The Duke meets Royal Marines who have completed a mammoth 1,664 mile trek on Wednesday - his final official royal event before he retires from public engagements. Picture by i-Images / Pool / eyevine

02/08/2017. London, United Kingdom. The Duke of Edinburgh attending the Captain General's Parade. The Duke of Edinburgh attending the Captain General's Parade as his final individual public engagement, at Buckingham Palace in London. The Duke meets Royal Marines who have completed a mammoth 1,664 mile trek on Wednesday - his final official royal event before he retires from public engagements. Picture by i-Images / Pool / eyevine

02/08/2017. London, United Kingdom. The Duke of Edinburgh attending the Captain General's Parade. The Duke of Edinburgh attends The Captain General's Parade on the Buckingham Palace Forecourt in London on Wednesday 2nd August 2017. The Captain General's Parade is The Dukes final individual Royal Engagement although he may choose to attend certain events, alongside The Queen, from time to time. The parade marked the finale of the Royal Marines 1664 Global Challenge which saw Royal Marines from around the country running 16.64 miles each day for 100 days, totalling a distance of 1664 miles. Picture by i-Images / Pool / eyevine

02/08/2017. London, United Kingdom. The Duke of Edinburgh attending the Captain General's Parade. The Duke of Edinburgh attends The Captain General's Parade on the Buckingham Palace Forecourt in London on Wednesday 2nd August 2017. The Captain General's Parade is The Dukes final individual Royal Engagement although he may choose to attend certain events, alongside The Queen, from time to time. The parade marked the finale of the Royal Marines 1664 Global Challenge which saw Royal Marines from around the country running 16.64 miles each day for 100 days, totalling a distance of 1664 miles. Picture by i-Images / Pool / eyevine

02/08/2017. London, United Kingdom. The Duke of Edinburgh attending the Captain General's Parade. The Duke of Edinburgh attends The Captain General's Parade on the Buckingham Palace Forecourt in London on Wednesday 2nd August 2017. The Captain General's Parade is The Dukes final individual Royal Engagement although he may choose to attend certain events, alongside The Queen, from time to time. The parade marked the finale of the Royal Marines 1664 Global Challenge which saw Royal Marines from around the country running 16.64 miles each day for 100 days, totalling a distance of 1664 miles. Picture by i-Images / Pool / eyevine

02/08/2017. London, United Kingdom. The Duke of Edinburgh attending the Captain General's Parade. The Duke of Edinburgh attends The Captain General's Parade on the Buckingham Palace Forecourt in London on Wednesday 2nd August 2017. The Captain General's Parade is The Dukes final individual Royal Engagement although he may choose to attend certain events, alongside The Queen, from time to time. The parade marked the finale of the Royal Marines 1664 Global Challenge which saw Royal Marines from around the country running 16.64 miles each day for 100 days, totalling a distance of 1664 miles. Picture by i-Images / Pool / eyevine

19/07/2017. London, United Kingdom. The Queen and Prince Philip Visit Canada House. Her Majesty Queen Elizabeth II and Prince Philip, the Duke of Edinburgh visit Canada House in Trafalgar Square to celebrate Canada's 150th anniversary of Confederation. Their Highnesses will view artefacts and displays celebrating Canada 150, including items from the Royal Archives and from the National Maritime Museum's exhibition Death in the Ice, which explores Sir John Franklin's final Arctic expedition. Picture by Pete Maclaine / i-Images / eyevine

14/07/2017. London, United Kingdom. King Felipe and Queen Letizia Farewell. HM The Queen Elizabeth II and the Duke of Edinburgh say goodbye to King Felipe and Queen Letizia at Buckingham Palace, after their 3 day state visit to London. Picture by i Images/ Pool / eyevine

14/07/2017. London, United Kingdom. State Visit Of The King And Queen Of Spain - Day 3. Queen Elizabeth II and Prince Philip, Duke of Edinburgh are seen during a State visit by the King and Queen of Spain on July 14, 2017 in London, England. This is the first state visit by the current King Felipe and Queen Letizia, the last being in 1986 with King Juan Carlos and Queen Sofia. Picture by i-Images / Pool / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 12/07/2017. London, United Kingdom. Ceremonial welcome for the king and Queen of Spain. HM The Queen Elizabeth II and The Duke of Edinburgh attend the Ceremonial Welcome for His Majesty King Felipe VI of Spain, accompanied by Her Majesty Queen Letizia on Horse Guards Parade. Picture by Andrew Parsons / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 12/07/2017. London, United Kingdom. Ceremonial welcome for the king and Queen of Spain. HM The Queen Elizabeth II and The Duke of Edinburgh attend the Ceremonial Welcome for His Majesty King Felipe VI of Spain, accompanied by Her Majesty Queen Letizia on Horse Guards Parade. Picture by Andrew Parsons / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 12/07/2017. London, United Kingdom. Spanish State Visit. Her Majesty Queen Elizabeth II and His Royal Highness the Duke of Edinburgh accompany the His Majesty King Felipe VI and Her Majesty Queen Letizia of Spain to Horse Guards Parade where Their Royal Highnesses will receive a Ceremonial Welcome. Picture by Pete Maclaine / Parsons Media / eyevine

12/07/2017. London, United Kingdom. Ceremonial welcome for the king and Queen of Spain. HM The Queen Elizabeth II and The Duke of Edinburgh attend the Ceremonial Welcome for His Majesty King Felipe VI of Spain, accompanied by Her Majesty Queen Letizia on Horse Guards Parade. Picture by Andrew Parsons / i-Images / eyevine

12/07/2017. London, United Kingdom. Ceremonial welcome for the king and Queen of Spain. HM The Queen Elizabeth II and The Duke of Edinburgh attend the Ceremonial Welcome for His Majesty King Felipe VI of Spain, accompanied by Her Majesty Queen Letizia on Horse Guards Parade. Picture by Andrew Parsons / i-Images / eyevine

12/07/2017. London, United Kingdom. king and Queen of Spain State visit to the UK. The Queen and The Duke of Edinburgh formally welcome His Majesty King Felipe VI of Spain at Horse Guards Parade on Wednesday 12th July 2017. Pictured: The King and Queen of Spain join The Queen and The Duke of Edinburgh for a state carriage procession along The Mall to Buckingham Palace. His Majesty King Felipe VI of Spain sat in the 1st Carriage with HRH Queen Elizabeth whilst Her Majesty Queen Letizia joined The Duke of Edinburgh in the 2nd Carriage Picture by i-Images / Pool / eyevine

12/07/2017. London, United Kingdom. king and Queen of Spain State visit to the UK. Britain's Queen Elizabeth II and Britain's Prince Philip, Duke of Edinburgh greet Spanish King Felipe VI and Queen Letizia at Buckingham Palace on the first day of the Spanish Royals three day state visit. Spanish King Felipe VI and Queen Letizia begin a state visit to Britain on Wednesday, as the two countries attempt to strengthen ties despite tensions over Britain's plans to leave the European Union Picture by i-Images / Pool / eyevine

12/07/2017. London, United Kingdom. king and Queen of Spain State visit to the UK. Britain's Queen Elizabeth II and Britain's Prince Philip, Duke of Edinburgh greet Spanish King Felipe VI and Queen Letizia at Buckingham Palace on the first day of the Spanish Royals three day state visit. Spanish King Felipe VI and Queen Letizia begin a state visit to Britain on Wednesday, as the two countries attempt to strengthen ties despite tensions over Britain's plans to leave the European Union Picture by i-Images / Pool / eyevine

12/07/2017. London, United Kingdom. king and Queen of Spain State visit to the UK. The King and Queen of Spain view a display of Spanish items from the Royal Collection with HRH The Queen and The Duke of Edinburgh at Buckingham Palace during the state Visit. Picture by i-Images / Pool / eyevine

12/07/2017. London, United Kingdom. king and Queen of Spain State visit to the UK. The Queen and The Duke of Edinburgh host a State Banquet for King Felipe and Queen Letizia of Spain at Buckingham Palace, London, UK, on the 12th July 2017. Picture by i-Images / Pool / eyevine

12/07/2017. London, United Kingdom. king and Queen of Spain State visit to the UK. The Queen and The Duke of Edinburgh formally welcome His Majesty King Felipe VI of Spain at Horse Guards Parade on Wednesday 12th July 2017. Pictured: The King and Queen of Spain join The Queen and The Duke of Edinburgh for a state carriage procession along The Mall to Buckingham Palace. His Majesty King Felipe VI of Spain sat in the 1st Carriage with HRH Queen Elizabeth whilst Her Majesty Queen Letizia joined The Duke of Edinburgh in the 2nd Carriage Picture by i-Images / Pool / eyevine

04/07/2017. Edinburgh, United Kingdom. The Duke of Edinburgh attends the annual garden party at the Palace of Holyroodhouse in Edinburgh. Picture by ROTA / i-Images / eyevine

04/07/2017. Edinburgh, United Kingdom. The Duke of Edinburgh attends the annual garden party at the Palace of Holyroodhouse in Edinburgh. Picture by ROTA / i-Images / eyevine

04/07/2017. Edinburgh, United Kingdom. The Duke of Edinburgh attends the annual garden party at the Palace of Holyroodhouse in Edinburgh. Picture by ROTA / i-Images / eyevine

04/07/2017. Edinburgh, United Kingdom. The Duke of Edinburgh attends the annual garden party at the Palace of Holyroodhouse in Edinburgh. Picture by ROTA / i-Images / eyevine

04/07/2017. Edinburgh, United Kingdom. The Duke of Edinburgh attends the annual garden party at the Palace of Holyroodhouse in Edinburgh. Picture by ROTA / i-Images / eyevine

FILE IMAGE : 06/07/2017. London, United Kingdom. The Duke of Edinburgh Gold Award. The Duke of Edinburgh attends the Presentation Reception for The Duke of Edinburgh Gold Award holders in the gardens at the Palace of Holyrood house in Edinburgh Picture by i-Images / Pool / eyevine

FILE IMAGE : 06/07/2017. London, United Kingdom. The Duke of Edinburgh Gold Award. The Duke of Edinburgh attends the Presentation Reception for The Duke of Edinburgh Gold Award holders in the gardens at the Palace of Holyroodhouse in Edinburgh Picture by i-Images / Pool / eyevine

FILE IMAGE : 06/07/2017. London, United Kingdom. The Duke of Edinburgh Gold Award. The Duke of Edinburgh attends the Presentation Reception for The Duke of Edinburgh Gold Award holders in the gardens at the Palace of Holyroodhouse in Edinburgh Picture by i-Images / Pool / eyevine

FILE IMAGE : 06/07/2017. London, United Kingdom. The Duke of Edinburgh Gold Award. The Duke of Edinburgh attends the Presentation Reception for The Duke of Edinburgh Gold Award holders in the gardens at the Palace of Holyrood house in Edinburgh Picture by i-Images / Pool / eyevine

FILE IMAGE : 06/07/2017. London, United Kingdom. The Duke of Edinburgh Gold Award. The Duke of Edinburgh attends the Presentation Reception for The Duke of Edinburgh Gold Award holders in the gardens at the Palace of Holyroodhouse in Edinburgh Picture by i-Images / Pool / eyevine

FILE IMAGE : 06/07/2017. London, United Kingdom. The Duke of Edinburgh Gold Award. The Duke of Edinburgh attends the Presentation Reception for The Duke of Edinburgh Gold Award holders in the gardens at the Palace of Holyrood house in Edinburgh Picture by i-Images / Pool / eyevine

FILE IMAGE : 06/07/2017. London, United Kingdom. The Duke of Edinburgh Gold Award. The Duke of Edinburgh attends the Presentation Reception for The Duke of Edinburgh Gold Award holders in the gardens at the Palace of Holyrood house in Edinburgh Picture by i-Images / Pool / eyevine

FILE IMAGE : 06/07/2017. London, United Kingdom. The Duke of Edinburgh Gold Award. The Duke of Edinburgh during the National Anthem before the Presentation Reception for The Duke of Edinburgh Gold Award holders in the gardens at the Palace of Holyrood house in Edinburgh Picture by i-Images / Pool / eyevine

27/06/2017. London, United Kingdom. The Duke of Edinburgh leaving the funeral of Countess Mountbatten of Burma at St.Paul's church in Knightsbridge, London. Picture by Stephen Lock / i-Images / eyevine

27/06/2017. London, United Kingdom. Countess Mountbatten of Burma Funeral. Britain's Queen Elizabeth accompanied by Prince Philip and Prince Charles attends the funeral of The Countess Mountbatten of Burma at St Paul's Church in Knightsbridge. Picture by i-Images / Pool / eyevine

20.06.2017, Royal Ascot, Windsor, GBR, GROSSBRITANNIEN - Royal Procession. Queen Elizabeth the Second and Prince Philipp arriving at the racecourse. Ascot racecourse. Queen Elisabeth, Prinz Philipp, Portrait, Portraet, Royals, Koenigin Elisabeth, Portrat, K?nigin Elisabeth 170620D017ROYALASCOT.JPG GALOPP

Image licensed to i-Images Picture Agency. 18/06/2017. Egham, United Kingdom. The Duke of Edinburgh arriving at the Cartier Queen's Cup Final at the Guards Polo club, Smith's Lawn, United Kingdom. Picture by Stephen Lock / i-Images / eyevine

Image licensed to i-Images Picture Agency. 18/06/2017. Egham, United Kingdom. The Queen and Duke of Edinburgh in the Royal box at the Cartier Queen's Cup Final at the Guards Polo club, Smith's Lawn, United Kingdom. Picture by Stephen Lock / i-Images / eyevine

Image licensed to i-Images Picture Agency. 18/06/2017. Egham, United Kingdom. The Duke of Edinburgh arriving at the Cartier Queen's Cup Final at the Guards Polo club, Smith's Lawn, United Kingdom. Picture by Stephen Lock / i-Images / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 17/06/2017. London, United Kingdom. Trooping the Colour. Prince George and Princess Charlotte join HM The Queen Elizabeth II and the Duke of Edinburgh on the balcony of Buckingham Palace for Trooping the Colour. Picture by Andrew Parsons / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 17/06/2017. London, United Kingdom. Trooping the Colour. The Duke and Duchess of Cambridge with their children Prince George and Princess Charlotte, join HM Queen Elizabeth II and the Duke of Edinburgh on the balcony of Buckingham Palace for the Tropping the Colour. Picture by Andrew Parsons / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 17/06/2017. London, United Kingdom. Trooping the Colour. The Duke and Duchess of Cambridge with their children Prince George and Princess Charlotte, join HM Queen Elizabeth II and the Duke of Edinburgh on the balcony of Buckingham Palace for the Tropping the Colour. Picture by Andrew Parsons / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 17/06/2017. London, United Kingdom. Trooping the Colour. Her Majesty Queen Elizabeth II and Prince Philip travel along the Mall in an open top carriage during the Trooping the Colour. Picture by Pete Maclaine / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 17/06/2017. London, United Kingdom. Trooping the Colour. The Duke and Duchess of Cambridge with their children Prince George and Princess Charlotte, join HM Queen Elizabeth II and the Duke of Edinburgh on the balcony of Buckingham Palace for the Tropping the Colour. Picture by Andrew Parsons / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 17/06/2017. London, United Kingdom. Trooping the Colour. Her Majesty Queen Elizabeth II and Prince Philip travel along the Mall in an open top carriage during the Trooping the Colour. Picture by Pete Maclaine / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 17/06/2017. London, United Kingdom. Trooping the Colour. Her Majesty Queen Elizabeth II and Prince Philip travel along the Mall in an open top carriage during the Trooping the Colour. Picture by Pete Maclaine / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 17/06/2017. London, United Kingdom. Trooping the Colour. Prince George and Princess Charlotte join HM The Queen Elizabeth II and the Duke of Edinburgh on the balcony of Buckingham Palace for Trooping the Colour. Picture by Andrew Parsons / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 17/06/2017. London, United Kingdom. Trooping the Colour. Her Majesty Queen Elizabeth II and Prince Philip travel along the Mall in an open top carriage during the Trooping the Colour. Picture by Pete Maclaine / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 17/06/2017. London, United Kingdom. Trooping the Colour. The Duke and Duchess of Cambridge with their children Prince George and Princess Charlotte, join HM Queen Elizabeth II and the Duke of Edinburgh on the balcony of Buckingham Palace for the Tropping the Colour. Picture by Andrew Parsons / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 17/06/2017. London, United Kingdom. Trooping the Colour. The Duke and Duchess of Cambridge with their children join HM Queen Elizabeth II and the Duke of Edinburgh on the balcony of Buckingham Palace for the Tropping the Colour. Picture by Andrew Parsons / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 17/06/2017. London, United Kingdom. Trooping the Colour. The Duke and Duchess of Cambridge with their children Prince George and Princess Charlotte, join HM Queen Elizabeth II and the Duke of Edinburgh on the balcony of Buckingham Palace for the Tropping the Colour. Picture by Andrew Parsons / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 17/06/2017. London, United Kingdom. Trooping the Colour. The Duke and Duchess of Cambridge with their children Prince George and Princess Charlotte, join HM Queen Elizabeth II and the Duke of Edinburgh on the balcony of Buckingham Palace for the Tropping the Colour. Picture by Andrew Parsons / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 17/06/2017. London, United Kingdom. Trooping the Colour. Her Majesty Queen Elizabeth II and Prince Philip travel along the Mall in an open top carriage during the Trooping the Colour. Picture by Pete Maclaine / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 17/06/2017. London, United Kingdom. Trooping the Colour. Her Majesty Queen Elizabeth II and Prince Philip travel along the Mall in an open top carriage during the Trooping the Colour. Picture by Pete Maclaine / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 17/06/2017. London, United Kingdom. Trooping the Colour. Her Majesty Queen Elizabeth II and Prince Philip travel along the Mall in an open top carriage during the Trooping the Colour. Picture by Pete Maclaine / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 17/06/2017. London, United Kingdom. Trooping the Colour. HM The Queen Elizabeth II and the Duke of Edinburgh leave Buckingham Palace for Trooping the Colour. Picture by Andrew Parsons / Parsons Media / eyevine

London, United Kingdom. Trooping the Colour. Her Majesty Queen Elizabeth II and Prince Philip travel along the Mall in an open top carriage during the Trooping the Colour. The Annual Trooping the Colour marking the Queen's official birthday from Buckingham Palace to Horse Guards Parade.Trooping the Colour is a ceremony performed by regiments of the British and Commonwealth armies. It has been a tradition of British infantry regiments since the 17th century, although the roots go back much earlier. On battlefields, a regiment's colours, or flags, were used as rallying points. Since 1748 Trooping the Colour has also marked the official birthday of the British sovereign. It is held in London annually on a Saturday in June on Horse Guards Parade by St. James's Park, and coincides with the publication of the Birthday Honours List. Among the audience are the Royal Family, invited guests, ticketholders and the general public. The colourful ceremony, also known as "The Queen's Birthday Parade", is broadcast live by the BBC. The Queen travels down The Mall from Buckingham Palace in a royal procession with a sovereign's escort of Household Cavalry (mounted troops or horse guards). After receiving a royal salute, she inspects her troops of the Household Division, both foot guards and horse guards, and the King's Troop, Royal Horse Artillery. Each year, one of the foot-guards regiments is selected to troop its colour through the ranks of guards. Then the entire Household Division assembly conducts a march past the Queen, who receives a salute from the saluting base. Parading with its guns, the King's Troop takes precedence as the mounted troops perform a walk-march and trot-past. The music is provided by the massed bands of the foot guards and the mounted bands of the Household Cavalry, together with a Corps of Drums, and occasionally pipers, totalling approximately 400 musicians. Returning to Buckingham Palace, the Queen watches a further march-past from outside the gates.

London, United Kingdom. Trooping the Colour. Her Majesty Queen Elizabeth II and Prince Philip travel along the Mall in an open top carriage during the Trooping the Colour. The Annual Trooping the Colour marking the Queen's official birthday from Buckingham Palace to Horse Guards Parade.Trooping the Colour is a ceremony performed by regiments of the British and Commonwealth armies. It has been a tradition of British infantry regiments since the 17th century, although the roots go back much earlier. On battlefields, a regiment's colours, or flags, were used as rallying points. Since 1748 Trooping the Colour has also marked the official birthday of the British sovereign. It is held in London annually on a Saturday in June on Horse Guards Parade by St. James's Park, and coincides with the publication of the Birthday Honours List. Among the audience are the Royal Family, invited guests, ticketholders and the general public. The colourful ceremony, also known as "The Queen's Birthday Parade", is broadcast live by the BBC. The Queen travels down The Mall from Buckingham Palace in a royal procession with a sovereign's escort of Household Cavalry (mounted troops or horse guards). After receiving a royal salute, she inspects her troops of the Household Division, both foot guards and horse guards, and the King's Troop, Royal Horse Artillery. Each year, one of the foot-guards regiments is selected to troop its colour through the ranks of guards. Then the entire Household Division assembly conducts a march past the Queen, who receives a salute from the saluting base. Parading with its guns, the King's Troop takes precedence as the mounted troops perform a walk-march and trot-past. The music is provided by the massed bands of the foot guards and the mounted bands of the Household Cavalry, together with a Corps of Drums, and occasionally pipers, totalling approximately 400 musicians. Returning to Buckingham Palace, the Queen watches a further march-past from outside the gates.

Queen Elizabeth II and Prince Philip, Duke of Edinburgh at the balcony of Buckingham Palace in London, on June 17, 2017, to attend Trooping the colour the Queens birthday parade Photo : Albert Nieboer / Netherlands OUT / Point de Vue OUT - NO WIRE SERVICE - Photo: Albert Nieboer/Royal Press Europe/RPE | usage worldwide

Queen Elizabeth II and Prince Philip, Duke of Edinburgh at the Mall to Buckingham Palace in London, on June 17, 2017, to attend Trooping the colour the Queens birthday parade Photo : Albert Nieboer / Netherlands OUT / Point de Vue OUT - NO WIRE SERVICE - Photo: Albert Nieboer/Royal Press Europe/RPE | usage worldwide

13/06/2017. Slough, United Kingdom. The Duke of Edinburgh arrives with The Queen at Slough railway station, United Kingdom, to mark the 175th anniversary of the first train journey by a British monarch. The Queen and the Duke travelled from Slough to London Paddington on a Great Western Railway train, recreating the historic journey made by Queen Victoria on 13th June 1842. Picture by Stephen Lock / i-Images / eyevine

13/06/2017. Slough, United Kingdom. The Duke of Edinburgh arrives with The Queen at Slough railway station, United Kingdom, to mark the 175th anniversary of the first train journey by a British monarch. The Queen and the Duke travelled from Slough to London Paddington on a Great Western Railway train, recreating the historic journey made by Queen Victoria on 13th June 1842. Picture by Stephen Lock / i-Images / eyevine

13/06/2017. Slough, United Kingdom. The Queen and the Duke of Edinburgh after travelling on a train from Slough railway station, United Kingdom, to mark the 175th anniversary of the first train journey by a British monarch. The Queen and the Duke travelled from Slough to London Paddington on a Great Western Railway train, recreating the historic journey made by Queen Victoria on 13th June 1842. Picture by ROTA / i-Images / eyevine

13/06/2017. Slough, United Kingdom. The Queen and the Duke of Edinburgh after travelling on a train from Slough railway station, United Kingdom, to mark the 175th anniversary of the first train journey by a British monarch. The Queen and the Duke travelled from Slough to London Paddington on a Great Western Railway train, recreating the historic journey made by Queen Victoria on 13th June 1842. Picture by ROTA / i-Images / eyevine

13/06/2017. Slough, United Kingdom. The Queen and the Duke of Edinburgh on a train travelling from Slough railway station, United Kingdom, to mark the 175th anniversary of the first train journey by a British monarch. The Queen and the Duke travelled from Slough to London Paddington on a Great Western Railway train, recreating the historic journey made by Queen Victoria on 13th June 1842. Picture by ROTA / i-Images / eyevine

01/06/2017. London, United Kingdom. Queen Elizabeth II and the Duke of Edinburgh arrive for a garden party at Buckingham Palace in London . Picture by ROTA / i-Images / eyevine

01/06/2017. London, United Kingdom. The Duke of Edinburgh at a garden party at Buckingham Palace in London . Picture by ROTA / i-Images / eyevine

Image licensed to i-Images Picture Agency. 31/05/2017. London, United Kingdom. The Duke of Edinburgh at a reception to celebrate the London Youth charity's 130th anniversary at Buckingham Palace in London. Picture by ROTA / i-Images / eyevine

23/05/2017. London, United Kingdom. Queen Elizabeth and the Duke of Edinburgh at a Garden Party at Buckingham Palace in London, where a minute's silence was observed for the victims of the Manchester terror attack. Picture by ROTA / i-Images / eyevine

23/05/2017. London, United Kingdom. The Duke of Edinburgh at a Garden Party at Buckingham Palace in London, where a minute's silence was observed for the victims of the Manchester terror attack. Picture by ROTA / i-Images / eyevine

23/05/2017. London, United Kingdom. Queen Elizabeth and the Duke of Edinburgh at a Garden Party at Buckingham Palace in London, where a minute's silence was observed for the victims of the Manchester terror attack. Picture by ROTA / i-Images / eyevine

23/05/2017. London, United Kingdom. Queen Elizabeth and the Duke of Edinburgh at a Garden Party at Buckingham Palace in London, where a minute's silence was observed for the victims of the Manchester terror attack. Picture by ROTA / i-Images / eyevine

23/05/2017. London, United Kingdom. The Duke of Edinburgh at a Garden Party at Buckingham Palace in London, where a minute's silence was observed for the victims of the Manchester terror attack. Picture by ROTA / i-Images / eyevine

Image licensed to i-Images Picture Agency. 16/05/2017. London, United Kingdom. The Duke of Edinburgh at a Garden party at Buckingham Palace in London. Picture by ROTA / i-Images / eyevine

16/05/2017. London, United Kingdom. The Queen and Duke of Edinburgh at a Garden party at Buckingham Palace in London. Picture by ROTA / i-Images / eyevine

16/05/2017. London, United Kingdom. The Queen and Duke of Edinburgh at a Garden party at Buckingham Palace in London. Picture by ROTA / i-Images / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 10/05/2017. Windsor, United Kingdom. The Duke of Edinburgh drives a horse drawn carriage as he arrives at the Royal Windsor Horse Show. The Royal Windsor Horse Show 2017 at Windsor Castle, Berkshire, UK. Picture by Ben Stevens / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 10/05/2017. Windsor, United Kingdom. The Duke of Edinburgh drives a horse drawn carriage as he arrives at the Royal Windsor Horse Show. The Royal Windsor Horse Show 2017 at Windsor Castle, Berkshire, UK. Picture by Ben Stevens / Parsons Media / eyevine

Prince Philip, Duke of Edinburgh, has died aged 99. FILE PHOTO: 10/05/2017. Windsor, United Kingdom. The Duke of Edinburgh drives a horse drawn carriage as he arrives at the Royal Windsor Horse Show. The Royal Windsor Horse Show 2017 at Windsor Castle, Berkshire, UK. Picture by Ben Stevens / Parsons Media / eyevine

10/05/2017. Windsor, United Kingdom. The Duke of Edinburgh drives a horse drawn carriage as he arrives at the Royal Windsor Horse Show. The Royal Windsor Horse Show 2017 at Windsor Castle, Berkshire, UK. Picture by Ben Stevens / i-Images / eyevine

10/05/2017. Windsor, United Kingdom. The Duke of Edinburgh drives a horse drawn carriage as he arrives at the Royal Windsor Horse Show. The Royal Windsor Horse Show 2017 at Windsor Castle, Berkshire, UK. Picture by Ben Stevens / i-Images / eyevine

Image licensed to i-Images Picture Agency. 09/05/2017. Pangbourne, United Kingdom. The Queen and The Duke of Edinburgh arriving at Pangbourne College in Berkshire, United Kingdom to celebrate the college's centenary. Picture by Stephen Lock / i-Images / eyevine

09/05/2017. Pangbourne, United Kingdom. The Queen and the Duke of Edinburgh watch a parade of pupils during a visit to Pangbourne College in Berkshire, United Kingdom to celebrate the college's centenary. Picture by Stephen Lock / i-Images / eyevine

09/05/2017. Pangbourne, United Kingdom. The Queen and the Duke of Edinburgh watch a parade of pupils during a visit to Pangbourne College in Berkshire, United Kingdom to celebrate the college's centenary. Picture by Stephen Lock / i-Images / eyevine

09/05/2017. London, United Kingdom. HM the Queen visits Pangbourne College. Britain's Prince Philip, Duke of Edinburgh visits Pangbourne College, in Berkshire County on May 9, 2017 on the occasion of the school's centenary Picture by i-Images / eyevine

09/05/2017. London, United Kingdom. HM the Queen visits Pangbourne College. Britain's Prince Philip, Duke of Edinburgh visits Pangbourne College, in Berkshire County on May 9, 2017 on the occasion of the school's centenary. Picture by i-Images / eyevine

04/05/2017. London, UK. Prince Philip leaves Buckingham Palace Following an announcement that he will no longer take part in official engagements. . Credit: Ben Cawthra / eyevine

04/05/2017. London, United Kingdom. The Duke of Edinburgh arriving back at Buckingham Palace in London after the announcement the he is to retire from public duties . Picture by Stephen Lock / i-Images / eyevine