Ukraine's president will visit eastern regions on Wednesday but has not responded to the invite.
Bomb threats to Kiev's transport system and public spaces have become an almost daily occurance
Russian president Vladimir Putin and Ukrainian leader Petro Poroshenko met a number of EU leaders on Friday, but there was little sign of progress in ceasefire negotiations
Poroshenko is to visit the key port of Mariupol after Kiev accused rebels of sporadic violations overnight
President Petro Poroshenko announced air strikes and artillery assaults on pro-Russian separatists in eastern regions following the end of a ceasefire.