Russian energy company Gazprom said it has "stopped supplying un-paid-for gas to Ukraine" this morning, according to reports in Russian media.
Gazprom said Ukraine has failed to pay for its gas supplies.
A Gazprom spokesperson told ITV News the company will now require all payments to be made in advance.
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Rain will affect most of the UK today, with Scotland remaining largely fine and brighter spells appearing in the east and south.
In a searingly emotive address, the president cast Hillary Clinton as the most qualified candidate to unify America as next US president.
The release is the second batch in a series of leaks that have rattled the Democratic Party.