TOPSHOT - Ukrainian President Petro Poroshenko (C) gestures in front of his supporters as he waits for presidential candidate Volodymyr Zelensky for a debate before a high-stakes run-off vote at Olympiysky Stadium in Kiev on April 14, 2019. - Ukraine's vote frontrunner Volodymyr Zelensky did not show up for a debate with his incumbent rival Petro Poroshenko at the Kiev's stadium, which seats over 70,000 people. The actor Volodymyr Zelensky's predictable no-show prompted President Petro Poroshenko to stage a one-man debate at Kiev's Olympic Stadium as several thousand supporters flooded a nearby square. (Photo by Sergei SUPINSKY / AFP)

TOPSHOT - Ukrainian President Petro Poroshenko (C) gestures in front of his supporters as he waits for presidential candidate Volodymyr Zelensky for a debate before a high-stakes run-off vote at Olympiysky Stadium in Kiev on April 14, 2019. - Ukraine's vote frontrunner Volodymyr Zelensky did not show up for a debate with his incumbent rival Petro Poroshenko at the Kiev's stadium, which seats over 70,000 people. The actor Volodymyr Zelensky's predictable no-show prompted President Petro Poroshenko to stage a one-man debate at Kiev's Olympic Stadium as several thousand supporters flooded a nearby square. (Photo by Sergei CHUZAVKOV / AFP)

TOPSHOT - Ukrainian President Petro Poroshenko (C-R) poses for a photo with his supporters before a high-stakes run-off vote at Olympiysky Stadium in Kiev on April 14, 2019. - Ukraine's vote frontrunner Volodymyr Zelensky did not show up for a debate with his incumbent rival Petro Poroshenko at the Kiev's stadium, which seats over 70,000 people. The actor Volodymyr Zelensky's predictable no-show prompted President Petro Poroshenko to stage a one-man debate at Kiev's Olympic Stadium as several thousand supporters flooded a nearby square. (Photo by Genya SAVILOV / AFP)