The last Ukrainian forces holed up in Mariupol's smashed Azovstal steelworks surrendered on Friday, Russia's Defense Ministry said, ending the most destructive siege of the war as Moscow fought to cement control over the Donbas region.

Hours before Russia's announcement on Friday, Ukrainian President Volodymyr Zelenskyy said the last defenders at the steelworks had been told by Ukraine's military that they could get out and save their lives.

Russia said there were 531 members of the last group that had given up. "The territory of the Azovstal metallurgical plant ... has been completely liberated," the ministry said in a statement, adding that a total of 2,439 defenders had surrendered in the past few days.