Fears that Russia could claw back a second chunk of former Soviet territory in Europe grew on Sunday night after Nato warned that Moscow’s troops were poised to move into a pro-Russian enclave of Moldova.

NATO’s top commander said that Russian troops massed on Ukraine’s eastern border were well placed to take Transdniester, a Russian-speaking enclave that has declared independence from the rest of Moldova.

About a third of Transdniester’s half-million people are ethnic Russians, many of whom want to return to rule from Moscow. To this day, the streets of the capital, Tiraspol, are decked out with statues of Lenin and other symbols of the Soviet Union, of which Moldova was a member until its break-up in 1991.

US Air Force Gen Philip Breedlove, who is NATO’s supreme allied commander in Europe, said that gave President Vladimir Putin a pretext to send troops in there as a “protection” force for ethnic Russians, just as he has done in Crimea.