Ukraine has secured the release of 144 of its soldiers as part of its biggest prisoner exchange since the start of the Russian invasion, according to Ukrainian military intelligence.
The release includes 95 troops that played a prominent role in the defence of Mariupol and its Azovstal steelworks before being encircled and unconditionally surrendering to Russian forces, intelligence officials said.
The officials also said most of the prisoners were badly wounded, hurt by gunshots and shrapnel, burned, and suffering fractured bones and amputated limbs.
Moscow did not comment on a prisoner swap.
The chief of the self-proclaimed Donetsk People's Republic in the east of Ukraine said it had secured the release of 144 soldiers.
The UK will provide an extra £1bn of military aid for Ukraine, offering equipment enabling the country to go on the front foot to regain lost territory.
The new funding amounts to a 77% increase on the £1.3bn already provided, with Prime Minister Boris Johnson claiming British support was "transforming Ukraine's defences" against the Russian onslaught.
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The British military presence in Estonia will also be bolstered as NATO dramatically escalates its ability to respond to Vladimir Putin's Russia.
Officials said this will ensure the UK can provide rapid reinforcements if needed, and deploy artillery, air defence and helicopters.
Mr Johnson said Vladimir Putin's hope that NATO would be diminished has been proven "completely wrong" by the joining of Sweden and Finland.
The nations are to become part of the defence alliance after Turkey withdrew its objections.
Mr Johnson said Russian President Mr Putin is getting "more NATO", not less, as a result of his actions in Ukraine.