Britain summoned Russia's ambassador to clarify reports of a Russian military incursion into Ukraine and a build-up of equipment near the border, the Foreign Office said.
Russian ambassador Alexander Yakovenko was summoned following reports that a small column of Russian armoured vehicles had crossed overnight into an area of Ukraine where pro-Moscow rebels are battling government forces.
Nato has accused the Kremlin of escalating the conflict in Ukraine.
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The murderer was shaking and appeared to be gasping for air for around 13 minutes before dying.
The positive results come after Chancellor Philip Hammond admitted the government is prepared to sell its stake at a loss to the taxpayer.