More than 1,000 Ukraine marines have surrendered in Mariupol, says Russia

Moscow makes claim as leaders of four countries bordering Russia arrive in Kyiv in show of support for Ukraine

• Russia-Ukraine war: latest updates

More than 1,000 Ukrainian marines defending the besieged city of Mariupol have surrendered and the port has been captured, Moscow has said, as the presidents of four countries bordering Russia arrived in Kyiv in a show of support for Ukraine.

In one of the most critical battles of the war, Russia's defence ministry said that on Wednesday 1,026 soldiers from Ukraine's 36th Marine Brigade, including 162 officers, had voluntarily laid down their arms" near the city's Ilyich iron and steelworks.