MOSCOW - Russia said its forces had pushed deeper into the eastern Ukrainian cities of Pokrovsk and Kupiansk on Tuesday, with one video showing Russian soldiers rolling into Pokrovsk on motorbikes and even on the roofs of battered cars and vans.

Moscow says taking Pokrovsk, dubbed "the gateway to Donetsk" by Russian media, would give it a platform to drive north towards the two biggest remaining Ukrainian-controlled cities in the Donetsk region - Kramatorsk and Sloviansk.