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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Terry Butcher said his son's life had been "tragically cut short" and described him as a "dedicated captain in the British Army".
Through the morning an area of rain will steadily track northeastwards across central England.
An outdoor nursery where children are only allowed to play with toys they have made themselves has been named Britain's Best Nursery.