Ukraine's presidential election is a "decisive signal of their support for reform", William Hague declared as he praised voters for defying disruption by pro-Russian separatists.
The Foreign Secretary said every vote cast was "an individual act of courage" as he pledged to work with the country's new leader on ambitious reforms.
Exit polls suggested a convincing win for billionaire chocolate tycoon Petro Poroshenko, who is said to have received 55.9% - with former prime minister Yulia Tymoshenko a distant second.
Voting was severely disrupted in parts of the east of the country, where separatists have seized control amid fighting that has claimed at least 20 lives in recent days.
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The twin brother of the police officer shot and blinded by gunman Raoul Moat says his family are still waiting for justice five years later.
The success of the No camp is mainly due to Tsipras convincing people a No vote will strengthen their hands in negotiations.
As we move into the weekend, expect things to get rather more unsettled weather-wise - thought it will stay hot and humid for some.