A satellite image shows an overview of Yablonska Street, in Bucha, Ukraine, March 31, 2022. Picture taken March 31, 2022. Satellite image 2022 Maxar Technologies/Handout via REUTERS
A satellite image shows an overview of Yablonska Street, in Bucha, Ukraine, March 31, 2022. Picture taken March 31, 2022. Satellite image 2022 Maxar Technologies/Handout via REUTERS Reuters / MAXAR TECHNOLOGIES

Russia on Tuesday pushed back against Western claims its soldiers had committed war crimes in Ukraine, casting such allegations as fake propaganda staged by Ukrainian special forces to besmirch Moscow.

Since Russian troops withdrew from towns and villages around the Ukrainian capital Kyiv, Ukrainian troops have been showing journalists corpses of what they say are civilians killed by Russian forces, destroyed houses and burnt-out cars.

The West says the dead civilians are evidence of war crimes. Reuters saw dead bodies in the town of Bucha but could not independently verify who was responsible for the killings.

"These are fakes that matured in the cynical imagination of Ukrainian propaganda," Dmitry Medvedev, who served as president from 2008 to 2012 and is now deputy secretary of Russia's Security Council, said on Telegram.

Russia's defence ministry said it had evidence that the 72nd Ukrainian Main Center for Psychological Operations had helped stage such propaganda in a village 23 km (14 miles) northwest of Kyiv as well as in Sumy, Konotop, and other towns.

"Soldiers of the 72nd Ukrainian Main Center for Psychological Operations conducted another staged filming of civilians allegedly killed by the violent actions of the Russian armed forces," the ministry said. It gave no further details.

The West has vowed to impose yet more sanctions on Russia after the discovery of so many dead civilians, some shot in the head, after Russia's withdrawal from areas around Kyiv.

U.S. President Joe Biden on Monday accused Russian President Vladimir Putin of war crimes and called for a trial.

"You saw what happened in Bucha," Biden told reporters after landing in Washington from Delaware, where he had spent the weekend. "This warrants him - he is a war criminal."

Russia has denied any role in the killings and the Kremlin has cast such rhetoric from Biden as unforgivable. It says a full investigation should be carried out into the situation in Bucha.

Moscow has questioned why, if its forces withdrew from Bucha on March 30 and the mayor of Bucha declared the area free of Russian forces on March 31, that the bodies of dead civilians were only shown for the first time on April 3.

Russia also says the bodies shown in some footage did not show characteristic signs of degradation that would be expected after a number of days.

Russia's Medvedev said the fakes had been concocted for vast amounts of money by Western public relations companies and "tame" non-governmental organisations. He did not provide specific evidence.

He suggested that Ukrainian forces had been prepared to kill their own citizens in a bid to discredit Russia.

"To dehumanise Russia and for her maximum vilification, the frenzied beasts from the national battalions and territorial defence units are prepared to kill even their own civilians," Medvedev said.

Putin says the "special military operation" in Ukraine is necessary because the United States was using Ukraine to threaten Russia and Moscow had to defend Russian-speaking people in Ukraine from persecution.

Ukraine has dismissed Putin's claims of persecution and says Russia is fighting an unprovoked war of aggression.