More than 1,000 Ukraine marines surrender in key port of Mariupol, says Russia

More than 1,000 Ukrainian marines have surrendered in the besieged port of Mariupol, Russia's defence ministry said on Wednesday of Moscow's main target in the eastern Donbas region which it has yet to bring under its control.

If the Russians take the Azovstal industrial district, where the marines have been holed up, they would be in full control of Mariupol, Ukraine's main Sea of Azov port, which would allow Russia to reinforce a land corridor between separatist-held eastern areas and the Crimea region that it seized and annexed in 2014.

Surrounded by Russian troops for weeks and the focus of some of the fiercest fighting of the war, Mariupol would be the first major city to fall since Russia invaded Ukraine on Feb. 24. The battle for the industrial heartland of Donbas is likely to define the course of the war.

Russia's defence ministry said that 1,026 soldiers of Ukraine's 36th Marine Brigade surrendered, including 162 officers.

Ukraine's general staff said Russian forces were proceeding with attacks on Azovstal and the port, but a defence ministry spokesman said he had no information about any surrender.

Reuters journalists accompanying Russian-backed separatists saw flames billowing from the Azovstal district on Tuesday.

On Monday, the 36th Marine Brigade said it was preparing for a final battle in Mariupol that would end in death or capture as its troops had run out of ammunition.

Thousands of people are believed to have been killed in Mariupol and Russia has been massing thousands of troops in the area for a new assault, Ukrainian President Volodymyr Zelenskiy said.

Ukraine says tens of thousands of civilians have been trapped inside the city with no way to bring in food or water, and accuses Russia of blocking aid convoys.