LONDON, Jan 20 (Reuters) - British Prime Minister Boris Johnson on Thursday warned Russia that any kind of incursion into Ukraine would be a disaster for the world, saying the London stood squarely behind the sovereignty and integrity of Ukraine. U.S. President Joe Biden predicted on Wednesday that Russia will make a move on Ukraine, saying Russia would pay dearly for a full-scale invasion but suggesting there could be a lower cost for a "minor incursion." read more Biden"s comments at a White House news conference injected uncertainty into how the West would respond should Russian President Vladimir Putin order an invasion of Ukraine, prompting the White House later to attempt to clarify what Biden meant. Asked about Biden"s comments, Johnson warned Moscow against any kind of incursion. "Be in no doubt that if Russia were to make any kind of incursion into Ukraine, on any scale whatever, I think that that would be a disaster, not just for Ukraine, but for Russia. It would be a disaster for the world," Johnson told broadcasters. "The UK stands squarely behind the sovereignty and integrity of Ukraine."