Ukrainian comedian Volodymyr Zelensky is set to become the country's next president.
With 42 per cent of ballots counted, exit polls showed that the political newcomer has won the run-off election by a landslide with more than 70 per cent support.
His rival, incumbent president Petro Poroshenko, has admitted defeat but told supporters he will not leave politics.
"I will never let you down," Zelensky told his supporters, adding, "I'm not yet officially the president. But as a citizen of Ukraine, I can say to all countries in the post-Soviet Union: Look at us. Anything is possible!"
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