Russia denies sending troops and weapons in to Ukraine
Ukraine says it has partially destroyed a column of armoured vehicles crossing the border from Russia. Nato said it was a military "incursion", and here the Foreign Office has summoned Russia's envoy to explain.
But Russia's defence ministry has denied any such column entered Ukraine.
Meanwhile the convoy of aid that has been sent by Russia is still parked south of the city of Kamensk-Shakhtinsky, from here the BBC's Steve Rosenberg reports.