Comedian Volodymyr Zelenskiy has won Ukraine’s presidential election with 73% of the vote, according to an exit poll.
The poll suggests Mr Zelenskiy has beaten Petro Poroshenko by a landslide with the incumbent winning just 25% of the vote.
Mr Poroshenko conceded defeat on Sunday and said he would leave office next month.
“I’m leaving office, but I want to make it clear that I’m not leaving politics,” he said.
Mr Zelenskiy, 41, who plays a president in a popular TV series, is set to take over the leadership of a country on the frontline of the West’s standoff with Russia following Moscow’s annexation of Crimea.
“We did it together,” he said after the exit poll was released, thanking his wife, parents and campaign team.
“Thanks to all the Ukrainian citizens who voted for me, and to all who didn’t: I promise I won’t mess up.”
Mr Zelenskiy has pledged to end the war in the eastern Donbass region and to root out corruption amid widespread fury over soaring prices and falling living standards.
Speaking after casting his vote, Mr Poroshenko had said: “It’s important to be guided by reason, not laughs.
“It could be funny first, but pain may come later.”
Mr Zelenskiy, who comes from Ukraine’s mostly Russian-speaking east, got twice as many votes as Mr Poroshenko in the first round of voting three weeks ago.
Speaking after voting in the Ukrainian capital, Mr Zelenskiy had said: “While I am not yet president, I can speak as a citizen of Ukraine: to all the countries of the former Soviet Union, look at us. Everything is possible.”
Corruption continued on a massive scale during Mr Poroshenko’s five years in office and a war with Russia-backed separatist rebels in the eastern part of the country has killed more than 13,000 people.