World Bulletin/News Desk

Britain summoned Russia's ambassador on Friday to clarify reports of a Russian military incursion into Ukraine and a build-up of equipment near the border, the Foreign Office said.

NATO has accused the Kremlin of escalating the conflict in Ukraine, 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.

The Foreign Office said in a statement that it had summoned Ambassador Alexander Yakovenko "to clarify reports of Russian military incursion into Ukraine".