In eastern Ukraine, at least one person was killed and several others injured as shelling continued in the rebel-held stronghold of Donestk on Wednesday.
Video footage showed a cultural centre caught fire and a residential building with a massive hole in the roof following the latest violence.
In the government-held town of Novoazovsk, more than 20 shells were fired in one hour.
Ukraine also said that fighting in the towns of Horlivka and Ilovaysk to the north and east respectively had killed about 200 pro-Russian separatists and 13 Ukrainian troops.
Meanwhile Ukraine accused Russia of launching a new incursion across its border after several Russian soldiers reportedly entered the border town of Amvrosiyivka in armoured infantry carriers.
The latest fighting dents hopes that Tuesday’s Minsk summit, between officials from Moscow and Kviv, could bring a quick end to five months of conflict.