ITV News Correspondent Dan Rivers reports on the latest in Ukraine as evidence of mass killings are uncovered around Kyiv
Vladimir Putin should face a war crimes trial after fresh allegations of atrocities committed by the Russian army, US President Joe Biden has said.
His comments come after Ukraine President Volodymyr Zelenskyy visited Bucha, one of the towns around Kyiv, where officials say the bodies of hundreds of civilians have been found.
Poland's Prime Minister Mateusz Morawiecki, meanwhile, compared Putin to Hitler as he criticised French President Emmanuel Macron for negotiating with him, as international leaders rounded on Russia.
“You saw what happened in Bucha,” Mr Biden said, adding that President Putin “is a war criminal".
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Mr Zelenskyy called the Russian actions “genocide” and called for the West to apply tougher sanctions against Russia, but Mr Biden stopped short of using the same term.
“We have to gather all the detail so this can be an actual - have a war crimes trial,” Mr Biden said.
"What’s happening in Bucha is outrageous and everyone sees it."
ITV News Reporter Dan Rivers says he has seen three mass graves and adds all the evidence points to Russia
The bodies of 410 civilians have been removed from Kyiv-area towns that were recently retaken from Russian forces, Ukraine’s prosecutor-general, Iryna Venediktova, said.
The allegations sparked Poland's prime minister to single out a number of leaders, including French President Emmanuel Macron and German Chancellor Olaf Scholz.
"How many times have you negotiated with Putin? What have you achieved? Have you stopped any of these actions that took place?" He asked of Mr Macron.
"Criminals are not to be discussed and negotiated with. Criminals must be fought."
Mr Zelenskyy, meanwhile, said Russia needs to move quickly to negotiate an agreement to end the war.
Speaking on a visit to Bucha, he said the evidence of atrocities makes it hard to conduct talks with Russia.
"It’s very difficult to conduct negotiations when you see what they did here,” he said, adding that in Bucha and other places “dead people have been found in barrels, basements, strangled, tortured".
He added that “the longer the Russian Federation drags it out, the worse it will exacerbate its own situation and this war".
He also warned residents that Russian forces were creating a “catastrophic” situation for civilians by leaving mines around homes, abandoned equipment and even corpses.
Amid his calls to western nations to take more action, Germany expelled 40 Russian envoys over the atrocities in Bucha and said further measures with allies are being prepared, while the US plans to seek a suspension of Russia from its seat on the UN’s top human rights body.
France too said it was expelling "a number" of diplomats.
What happened outside Kyiv?
Ukrainian authorities have said that the bodies of at least 410 civilians have been found in areas outside the Ukrainian capital after last week’s withdrawal of Russian troops — many with bound hands, close-range gunshot wounds and signs of torture.
ITV News Correspondent Dan Rivers is in Bucha where "atrocities on a sickening scale are being uncovered."
He had heard accounts of rape and mass executions, and was shown mass graves in the city after the Russians withdrew.
Some of the dead were buried by friends near their homes in marked graves, but many more were hastily interned in mass graves, with no headstones or even identification.
One grave he was shown held around 280 bodies in two rows - one side for dead Russians and the other for Ukrainians.
One man told Dan Rivers of the rape and murder of a young woman at the hands of two Chechen soldiers who he and another man later killed.
A day earlier, journalists witnessed Ukrainian soldiers gingerly removing at least six bodies from a street in Bucha with cables in case the Russians had booby-trapped corpses with explosives before their withdrawal.
Local residents said the dead people were civilians killed without provocation, a claim that could not be independently verified
Russia has rejected the accusations of killing civilians as a “provocation” by Ukrainian authorities and initiated a meeting of the UN Security Council to discuss the issue.
The country's ambassador to the United Nations, Vassily Nebenzia, dismissed the reports as "fake news" - though his claims are widely disbelieved.
"On April 4, the Kyiv regime, with an active support form western sponsors, start to promote in western mass media fake news about alleged atrocities by Russian military forces in the town of Bucha.
"From the very beginning it has been clear that is nothing else but a staged provocation aimed at discrediting and dehumanising of the Russian military and levelling political pressure on Russia."
What has the UK said?
Boris Johnson’s spokesperson said bodies found in areas recently recaptured from Russia showed “despicable attacks against innocent civilians, and they are yet more evidence that Putin and his army are committing what appear to be war crimes in Ukraine".
But he stopped short of calling it genocide. The spokesperson said “the prime minister’s view is that Putin crossed the threshold of barbarism some time ago", but added that only a court can make a determination of genocide.
Britain is urging Western allies to enforce tougher sanctions to “ratchet up” pressure on Russia, including cutting it off completely from the SWIFT international payments system.
More civilian deaths reported
More civilian casualties were reported by Ukraine on Sunday.
At least seven people were killed and 34, including three children, were wounded in a Russian rocket attack on Ukraine’s second-largest city of Kharkiv, according to the regional prosecutor’s office.
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It said that 10 buildings were destroyed.
In the Black Sea port of Mykolaiv, regional Governor Vitaliy Kim said at least one resident was killed and 14 others were wounded by Russian shelling on Sunday night.
Local authorities also reported more Russian strikes on Mykolaiv early on Monday, but there was no immediate word of casualties.
Russian forces continue to withdraw across Ukraine.
Russian troops withdrew from the Sumy region in Ukraine’s northeast, which they had occupied for nearly a month, local administrator Dmitry Zhivitsky said in a video message carried by Ukrainian news agencies on Sunday.
Meanwhile, news agency RBK Ukraina said the road between Chernihiv and the capital of Kyiv is to reopen to some traffic later on Monday. The mayor said on Sunday that relentless Russian shelling had destroyed 70% of the city.