A handout photograph released by the UK Parliament shows Britain's Prime Minister Theresa May answering questions after making a statement to the House of Commons in London on December 17, 2018, following her attendance at an EU Summit last week. - Prime Minister Theresa May will on Monday warn MPs against supporting a second Brexit referendum, as calls mount for a public vote to break the political impasse over the deal she struck with the EU. "Let us not break faith with the British people by trying to stage another referendum," she will tell parliament, according to extracts from her speech released by Downing Street. (Photo by Jessica TAYLOR / UK PARLIAMENT / AFP) / RESTRICTED TO EDITORIAL USE - NO USE FOR ENTERTAINMENT, SATIRICAL, ADVERTISING PURPOSES - MANDATORY CREDIT " AFP PHOTO / Jessica Taylor /UK Parliament"

A handout photograph released by the UK Parliament shows Britain's Prime Minister Theresa May answering questions after making a statement to the House of Commons in London on December 17, 2018, following her attendance at an EU Summit last week. - Prime Minister Theresa May will on Monday warn MPs against supporting a second Brexit referendum, as calls mount for a public vote to break the political impasse over the deal she struck with the EU. "Let us not break faith with the British people by trying to stage another referendum," she will tell parliament, according to extracts from her speech released by Downing Street. (Photo by Jessica TAYLOR / UK PARLIAMENT / AFP) / RESTRICTED TO EDITORIAL USE - NO USE FOR ENTERTAINMENT, SATIRICAL, ADVERTISING PURPOSES - MANDATORY CREDIT " AFP PHOTO / Jessica Taylor /UK Parliament"

A handout photograph released by the UK Parliament shows Britain's Prime Minister Theresa May (centre left) answering questions after making a statement to the House of Commons in London on December 17, 2018, following her attendance at an EU Summit last week. - Prime Minister Theresa May will on Monday warn MPs against supporting a second Brexit referendum, as calls mount for a public vote to break the political impasse over the deal she struck with the EU. "Let us not break faith with the British people by trying to stage another referendum," she will tell parliament, according to extracts from her speech released by Downing Street. (Photo by Jessica TAYLOR / UK PARLIAMENT / AFP) / RESTRICTED TO EDITORIAL USE - NO USE FOR ENTERTAINMENT, SATIRICAL, ADVERTISING PURPOSES - MANDATORY CREDIT " AFP PHOTO / Jessica Taylor /UK Parliament"

A handout photograph released by the UK Parliament shows Britain's Prime Minister Theresa May (top right) reacting as oppossition Labour Party leader Jeremy Corbyn (C) replies to her statement to the House of Commons in London on December 17, 2018, following her attendance at an EU Summit last week. - Prime Minister Theresa May will on Monday warn MPs against supporting a second Brexit referendum, as calls mount for a public vote to break the political impasse over the deal she struck with the EU. "Let us not break faith with the British people by trying to stage another referendum," she will tell parliament, according to extracts from her speech released by Downing Street. (Photo by Jessica TAYLOR / UK PARLIAMENT / AFP) / RESTRICTED TO EDITORIAL USE - NO USE FOR ENTERTAINMENT, SATIRICAL, ADVERTISING PURPOSES - MANDATORY CREDIT " AFP PHOTO / Jessica Taylor /UK Parliament"

A handout photograph released by the UK Parliament shows Britain's Prime Minister Theresa May making a statement to the House of Commons in London on December 17, 2018, following her attendance at an EU Summit last week. - Prime Minister Theresa May will on Monday warn MPs against supporting a second Brexit referendum, as calls mount for a public vote to break the political impasse over the deal she struck with the EU. "Let us not break faith with the British people by trying to stage another referendum," she will tell parliament, according to extracts from her speech released by Downing Street. (Photo by Jessica TAYLOR / UK PARLIAMENT / AFP) / RESTRICTED TO EDITORIAL USE - NO USE FOR ENTERTAINMENT, SATIRICAL, ADVERTISING PURPOSES - MANDATORY CREDIT " AFP PHOTO / Jessica Taylor /UK Parliament"

A handout photograph released by the UK Parliament shows Britain's Prime Minister Theresa May making a statement to the House of Commons in London on December 17, 2018, following her attendance at an EU Summit last week. - Prime Minister Theresa May will on Monday warn MPs against supporting a second Brexit referendum, as calls mount for a public vote to break the political impasse over the deal she struck with the EU. "Let us not break faith with the British people by trying to stage another referendum," she will tell parliament, according to extracts from her speech released by Downing Street. (Photo by Jessica TAYLOR / UK PARLIAMENT / AFP) / RESTRICTED TO EDITORIAL USE - NO USE FOR ENTERTAINMENT, SATIRICAL, ADVERTISING PURPOSES - MANDATORY CREDIT " AFP PHOTO / Jessica Taylor /UK Parliament"

A handout photograph released by the UK Parliament shows Britain's Prime Minister Theresa May (C) making a statement to the House of Commons in London on December 17, 2018, following her attendance at an EU Summit last week. - Prime Minister Theresa May will on Monday warn MPs against supporting a second Brexit referendum, as calls mount for a public vote to break the political impasse over the deal she struck with the EU. "Let us not break faith with the British people by trying to stage another referendum," she will tell parliament, according to extracts from her speech released by Downing Street. (Photo by Jessica TAYLOR / UK PARLIAMENT / AFP) / RESTRICTED TO EDITORIAL USE - NO USE FOR ENTERTAINMENT, SATIRICAL, ADVERTISING PURPOSES - MANDATORY CREDIT " AFP PHOTO / Jessica Taylor /UK Parliament"

A handout photograph released by the UK Parliament shows Britain's Prime Minister Theresa May smiling as she makes a statement to the House of Commons in London on December 17, 2018, following her attendance at an EU Summit last week. - Prime Minister Theresa May will on Monday warn MPs against supporting a second Brexit referendum, as calls mount for a public vote to break the political impasse over the deal she struck with the EU. "Let us not break faith with the British people by trying to stage another referendum," she will tell parliament, according to extracts from her speech released by Downing Street. (Photo by Jessica TAYLOR / UK PARLIAMENT / AFP) / RESTRICTED TO EDITORIAL USE - NO USE FOR ENTERTAINMENT, SATIRICAL, ADVERTISING PURPOSES - MANDATORY CREDIT " AFP PHOTO / Jessica Taylor /UK Parliament"

A handout photograph released by the UK Parliament shows Britain's Prime Minister Theresa May (L) talking to speaker of the House, John Bercow as she arrives to make a statement to the House of Commons in London on December 17, 2018, following her attendance at an EU Summit last week. - Prime Minister Theresa May will on Monday warn MPs against supporting a second Brexit referendum, as calls mount for a public vote to break the political impasse over the deal she struck with the EU. "Let us not break faith with the British people by trying to stage another referendum," she will tell parliament, according to extracts from her speech released by Downing Street. (Photo by Jessica TAYLOR / UK PARLIAMENT / AFP) / RESTRICTED TO EDITORIAL USE - NO USE FOR ENTERTAINMENT, SATIRICAL, ADVERTISING PURPOSES - MANDATORY CREDIT " AFP PHOTO / Jessica Taylor /UK Parliament"

A handout photograph released by the UK Parliament shows Britain's Prime Minister Theresa May answering questions after making a statement to the House of Commons in London on December 17, 2018, following her attendance at an EU Summit last week. - Prime Minister Theresa May will on Monday warn MPs against supporting a second Brexit referendum, as calls mount for a public vote to break the political impasse over the deal she struck with the EU. "Let us not break faith with the British people by trying to stage another referendum," she will tell parliament, according to extracts from her speech released by Downing Street. (Photo by Jessica TAYLOR / UK PARLIAMENT / AFP) / RESTRICTED TO EDITORIAL USE - NO USE FOR ENTERTAINMENT, SATIRICAL, ADVERTISING PURPOSES - MANDATORY CREDIT " AFP PHOTO / Jessica Taylor /UK Parliament"

A handout photograph released by the UK Parliament shows Britain's Prime Minister Theresa May answering questions after making a statement to the House of Commons in London on December 17, 2018, following her attendance at an EU Summit last week. - Prime Minister Theresa May will on Monday warn MPs against supporting a second Brexit referendum, as calls mount for a public vote to break the political impasse over the deal she struck with the EU. "Let us not break faith with the British people by trying to stage another referendum," she will tell parliament, according to extracts from her speech released by Downing Street. (Photo by Jessica TAYLOR / UK PARLIAMENT / AFP) / RESTRICTED TO EDITORIAL USE - NO USE FOR ENTERTAINMENT, SATIRICAL, ADVERTISING PURPOSES - MANDATORY CREDIT " AFP PHOTO / Jessica Taylor /UK Parliament"