Russia said Tuesday that 265 Ukrainian soldiers had surrendered after staging a last stand at the besieged Azovstal steelworks in Mariupol, prompting Kyiv to call for a prisoner exchange.
Moscow claimed control of the strategic port city last month after a weeks-long siege, but hundreds of Ukrainian soldiers remained holed up in tunnels beneath the huge Azovstal industrial zone.
"Over the past 24 hours, 265 militants laid down their arms and surrendered, including 51 heavily wounded," the Russian defence ministry said.
Publishing images showing wounded soldiers being carried on stretchers, it said the injured were taken to a hospital in the eastern Donetsk region controlled by pro-Kremlin rebels.
Elsewhere, lawmakers in Finland -- which shares a 1,300-kilometre (800-mile) border with Russia -- voted overwhelmingly in favour of joining the NATO military alliance.
The vote paves the way for a joint application with Sweden to be submitted on Wednesday, amid fears they could be Russia's next targets.
Meanwhile, Kyiv said negotiations with Russia on ending the near three-month war, which has killed thousands and sent millions fleeing, were "on hold", blaming Moscow for failing to compromise.
- ICC deployment -
Ukraine's defence ministry confirmed the soldiers had left Azovstal, expressing hope for an "exchange procedure... to repatriate these Ukrainian heroes as quickly as possible".
For those remaining in the warren of tunnels underneath the steelworks, it said it was doing "everything necessary for their rescue" -- although a military intervention was not possible.
In Moscow, Kremlin spokesman Dmitry Peskov did not answer questions about whether the Azovstal soldiers would be treated as war criminals or prisoners of war.
President Vladimir Putin "guaranteed that they would be treated according to the relevant international laws," he said.
Ukraine has accused Moscow of war crimes during the conflict, notably in the town of Bucha near Kyiv, where AFP reporters saw at least 20 bodies lying in the streets after Russian forces withdrew in late March.
The International Criminal Court said Tuesday it was deploying its largest-ever field team to Ukraine, comprising 42 investigators, forensic experts and support staff.
- 'Trying to stay alive' -
Ukraine's army said holding the steelworks had delayed the transfer of 20,000 Russian troops to other parts of the country and stopped Moscow from quickly capturing the southern city of Zaporizhzhia.
"Eighty-three days of Mariupol defence will go down in history as the Thermopylae of the 21st century," presidential aide Mykhaylo Podolyak said, referring to the last stand by the Spartans against the Persians in 480 BC.
Ukrainian forces have managed to fight the huge Russian army for longer than many expected, fortified by weapons and cash from Western allies.
French President Emmanuel Macron told Ukrainian counterpart Volodymyr Zelensky Tuesday during a telephone call that arms deliveries from Paris would "increase in intensity" in the coming weeks.
Zelensky said the two leaders also discussed fuel supplies to Ukraine, ways to export Ukrainian agricultural products and Kyiv's application to join the European Union, which Macron has said could take decades.
After circling the capital Kyiv in the early weeks of the war, Moscow has focused increasingly on the eastern region of Donbas.
Ukrainian officials say Russian troops are withdrawing from around Kharkiv, the country's second-largest city, to be redeployed there.
But Kyiv's gains have come at a high cost, with villages gutted and destroyed by bombs.
In Ruska Lozova, just north of Kharkiv, Rostislav Stepanenko recounted to AFP how he had gone back to collect some belongings but returned empty-handed and stunned by the incessant artillery fire.
Asked what he did for a living, he joked he was "trying to stay alive".
- 'Shelling without stopping' -
Ukraine says Russia is targeting Donbas areas including Severodonetsk, the easternmost city held by Ukrainian forces.
Control of Severodonetsk would grant the Kremlin de facto control of Lugansk, one of two regions -- along with Donetsk -- that comprise Donbas.
Russia's attempt to completely encircle Severodonetsk has been repelled, with Ukrainian forces blowing up railway bridges to slow their advance.
But Lugansk regional governor Sergiy Gaiday has said it was being shelled "without stopping" and two buildings at the city's general hospital had been hit overnight.
"We have 10 dead and three wounded in the region," he wrote on Telegram.
Elsewhere, eight people were killed and 12 injured in Russian strikes on the village of Desna, in northeastern Chernigiv region, where a Ukrainian military base is located, emergency services said.
As well as mourning its recent war dead, Ukraine held Tuesday a solemn funeral in Kyiv for Leonid Kravchuk, who this month died aged 88 and led Ukraine to independence from the Soviet Union in 1991.
An emotional Zelensky laid a wreath of flowers by Kravchuk's coffin, which was draped in a Ukrainian flag, while soldiers guarded the casket and a large photograph of Kravchuk stood behind them.
- New NATO bids -
Fearful of Russia's ambitions, Sweden and Finland are poised to give up decades of military non-alignment and join NATO.
Their bids must be unanimously approved by the alliance's 30 nations, but Turkish President Recep Tayyip Erdogan has objected, accusing the Nordic nations of harbouring terror groups.
US Secretary of State Antony Blinken has voiced confidence the bids will succeed and is due to meet Turkey's foreign minister in Washington Wednesday.
Western nations have also sought to punish Russia with unprecedented economic sanctions, with the EU mulling a ban on Russian oil.
Hungary is blocking the ban, citing the cost, and Putin claimed Tuesday Europe risked committing "economic suicide".
Many EU nations are also dependent on Russian gas but are in a quandary after Moscow demanded payment in rubles to circumvent the sanctions.
Finland's state-owned gas company Gasum said Tuesday Russia could cut gas supplies to the Nordic nation over its refusal to pay Gazprom in rubles. Russia has already stopped supplying electricity to Finland.
Italian energy giant Eni announced a potential workaround Tuesday involving opening two accounts with Russian energy firm Gazprom's bank. It proposed making payments in euros which would be converted into rubles through the Moscow stock exchange.