Comedian Volodymyr Zelenskiy, who plays Ukraine's president on television, has won the first round of the struggling country's presidential election and is set to face the incumbent in a runoff this month.
The political newcomer had garnered more than 30 per cent of Sunday's vote with four-fifths of the ballots counted on Monday afternoon. President Petro Poroshenko, known as 'the chocolate king' for his expansive candy business, was in second place with 16 per cent.
Former prime minister Yulia Tymoshenko was expected to miss the runoff with 13 per cent of the vote, even though she has claimed that her own parallel vote count has her advancing to the second round.
On Sunday night, she suggested she would dispute the results and called for supporters to come to polling places to prevent alleged falsifications for Mr Poroshenko
A simmering conflict with Russia-backed separatists in the east continues to plague Ukraine, which last year became the poorest country in Europe.
There has been agonisingly slow progress on reforms undertaken after a pro-Russian president was ousted by protests in 2014 and Crimea was annexed by Russia.
Surveys in March suggested that Mr Zelenskiy would handily defeat Mr Poroshenko if they faced each other in the second round.
The leading candidate has promised to tackle corruption but shunned a detailed platform and campaign in favour of a feel-good comedy tour.
Mr Poroshenko declared that he would win the runoff, calling Mr Zelenskiy a marionette of Ihor Kolomoisky, the self-exiled oligarch who owns the channel that runs his programmes.
Mr Zelenskiy responded by calling Mr Poroshenko a marionette of the former deputy head of his security council, a reference to a corruption scandal in which the official's son was found to have sold the defence ministry overpriced equipment smuggled in from Russia.
The comedian has been hit by his own scandals. A company he owns was found to have made money in Russia after he said he had no business there, and an investigation on Thursday found he owned an undeclared 15-room villa in an Italian resort favoured by Russian oligarchs.
Mr Zelensiky has said he would sit down with Vladimir Putin, the Russian president, to solve the conflict in eastern Ukraine. Asked by journalists on Sunday night what he would say to Mr Putin, he said he would force him to give back Ukrainian territory and demand compensation for occupying it.
Mr Putin's spokesman said on Monday that the leader would explain that Russia is not occupying Ukrainian territory, adding that Crimea was “not open for discussion”.
Spanish and Canadian warships docked in Odessa on Monday as part of a Nato mission to the Black Sea following last year's Kerch Strait crisis. Russia in November seized three Ukrainian ships near annexed Crimea and captured 24 sailors who are now on trial in Moscow.
Mr Poroshenko is expected to focus on Mr Zelenskiy's lack of experience and try to embarrass him in debates in the second round. An influx of cash subsidies to pensioners could also help mobilise support.
His challenger tried to appeal to disaffected voters by focusing on the president's business empire and corruption allegations against him. Only nine per cent of Ukrainians support their government, according to polls.
Reports emerged on Sunday that Mr Zelenskiy might form a parliamentary coalition with Ms Tymoshenko, which would set her up to become prime minister. Both candidates denied they were in talks.
Much of the country's opposition would support Mr Zelenskiy and try to turn the second round into a referendum on Mr Poroshenko, whose disapproval rating is up to 50 per cent, analyst Volodymyr Fesenko said.
“I would bet on Zelenskiy in second round, there are risks but he has more of a chance,” Mr Fesenko said. “It will depend on the turnout of his voters and how unified the opposition is, but there is a lot of dissatisfaction with Poroshenko.”