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Russia has called for a special UN Security Council meeting to address claims that its forces committed atrocities against Ukrainian civilians in Bucha.
On Sunday, Dmitry Polyanskiy, Russia's deputy ambassador to the UN, requested a meeting of the council “in the light of heinous provocation of Ukrainian radicals”, he said in a post on Twitter.
Ukraine and Western leaders have expressed outrage over the discovery of mass graves and hundreds of dead people in the small town north-west of Kyiv. Ukrainian President Volodymyr Zelenskyy directly blamed Moscow for the “killings” of civilians.
AP journalists saw at least 21 corpses in Bucha, with hands tied behind their backs. The European Union joined Mr Zelenskyy in holding Russia responsible for the deaths the civilians, by some accounts as many as 300 killings.
"Shocked by news of atrocities committed by Russian forces. EU assists Ukraine in documenting war crimes," EU foreign policy chief Josep Borrell said on Twitter.
Mr Borrell called for cases to be "pursued" by the International Court of Justice.
Russia denied the accusations and said Kyiv staged footage of the corpses.
Senior Washington official Samantha Power, a former US ambassador to the UN, criticised Moscow's UN move and said it was designed to “feign outrage”.
“Russia is drawing from the playbook it used for Crimea and Aleppo,” Ms Power, the administrator of the US Agency for International Development, wrote on Twitter.
Ukraine said on Saturday its forces had retaken all areas around Kyiv, claiming complete control of the capital region for the first time since Russia launched its invasion on February 24.
UN authorities have yet to publicly state whether a Security Council emergency meeting will take place on Monday.
On Monday and Tuesday, a delegation of Arab League foreign ministers will meet their Russian and Ukrainian counterparts to seek a diplomatic solution to the war.