Ukraine’s access to weapons could determine fate of Donbas offensive

Analysis: As Russian troops turn to Donbas, Ukraine's pleas for munitions continue

• Russia-Ukraine war: latest updates

Russia and Ukraine both declared that Moscow's offensive in the Donbas region had begun this week - although, in reality, the air and artillery bombardment by Moscow's forces over the past 48 hours is not yet the intensive attack signalled by the Kremlin when it abandoned its attempt to seize Kyiv.

The strategy is well known: Russia aims to mass its previously overextended forces in the east of the country, where it hopes to gain an advantage of two or perhaps three to one over the Ukrainian defenders, encircling them by attacking south from Izium and, once Mariupol falls, pushing up from there north.