LONDON, Sept 23 (Reuters) - Russia will on Friday begin its plan to annex around 15% of Ukrainian territory via referendums in four regions controlled by Russian forces, a move the West says is a gross violation of international law that significantly escalates the war. Putin, Russia's paramount leader since 1999, said Russia would never abandon those in the regions it controls and whom he said wanted to secede from Kyiv. In a direct nuclear warning to the West, Putin said he would defend Russian territory - and these regions of Ukraine will be considered Russian territory by Moscow shortly - with all means at his disposal. 'SHAM VOTES'It is unclear exactly how the votes will work in a war zone when so many people have been displaced. "As of next week, Russia will consider these Ukrainian territories as being part of Russia, and they will claim any Ukrainian attempts to retake their own sovereign territory as an 'invasion of Russia'," Britain's Cleverly said.

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