president zelensky says peace talks with russia will come to a halt if russian forces kill all of the ukrainian troops defending mariupol. russia now claims to have cleared the whole urban area of the besieged city, with the exception of the azovstal metal works adjoining the port. meanwhile, the mayor of kyiv is warning residents not to return, following another missile attack on saturday. from there, our correspondent, mark lowen, reports. russian revenge. an early morning strike on a military factory in kyiv by long range missiles. a message from moscow that russian troops may have retreated from the capital, but they can still hit hard. it came after ukraine says it struck and sank