Russian President Vladimir Putin on Thursday claimed the "liberation" of the flattened city of Mariupol after nearly two months of fighting, demanding its trapped Ukrainian defenders be sealed into their underground last stand.
The fate of the besieged port has become totemic as Russia battles to complete a land bridge covering territories already under its control, including Crimea -- which would deprive Ukraine of its industrial heartland and most of its coastline.
Read more: Ukraine calls for talks in teetering Mariupol as Moscow holds ICBM test
President Joe Biden, however, said Putin was doomed to failure, announcing $800 million (740 million euros) in extra US military aid including howitzers and tactical drones.
"Our unity at home with our allies and partners, and our unity with the Ukrainian people, is sending an unmistakable message to Putin -- he will never succeed in dominating and occupying all of Ukraine," he said.
Ukraine appealed for an immediate humanitarian corridor to allow civilians and wounded fighters to be evacuated from Mariupol s sprawling Azovstal steel plant.
"They have almost no food, water, essential medicine," Ukraine s foreign ministry said.
Three school buses filled with Mariupol evacuees including women and children arrived in the city of Zaporizhzhia after crossing through territory held by Russian forces.
Exhausted evacuee Valentina, 73, told AFP she urgently needed medication for her back as she struggled to remain standing.
"My apartment has been destroyed just like the house of my son," she said, still wearing her slippers along with a torn black coat.
