The Russian defence ministry said it would open a humanitarian corridor earlier on Monday for all civilians to leave the Azovstal steel plant in the besieged port city of Mariupol. Ukraine’s deputy prime minister, Iryna Vereshchuk, said Kyiv had not reached an agreement with Moscow on creating a humanitarian corridor and said the UN should act as the “initiator and guarantor” of any agreement with Russia on evacuating civilians from the plant.