Ukrainian Prime Minister Arseny Yatseniuk blamed the breakdown of talks in a gas pricing dispute on Russia, saying Moscow had hoped to cause Kiev problems in winter.
"But it is not about gas. It is a general Russian plan to destroy Ukraine," Yatseniuk said.
Ukraine's energy minister said Russia had cut off all gas supplies to Kiev this morning after the two countries failed to reach an agreement on gas prices.
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The chancellor now faces the prospect of forming a minority government or calling for a snap election.
The 73-year-old said a return is unlikely "given the politicised atmosphere that seems to have afflicted our set."
Chancellor Philip Hammond said the UK will make a financial proposal to the EU in the next three-and-a-half weeks.