WASHINGTON, April 4 — US President Joe Biden called Russian President Vladimir Putin a war criminal today and urged holding a war crimes trial, as a global outcry mounted over civilian killings in the Ukrainian town of Bucha.

"You saw what happened in Bucha,” Biden told reporters at the White House. "This warrants him - he is a war criminal.”

The discovery of a mass grave and tied bodies shot at close range in Bucha, outside Kyiv, a town taken back from Russian troops, looked set to galvanise the United States and Europe into additional sanctions against Moscow.

Biden said, "We have to gather the information. We have to continue to provide Ukraine with the weapons they need to continue the fight. And we have to get all the detail so this can be an actual, have a war crimes trial.”

Putin "is brutal. And what’s happening in Bucha is outrageous, and everyone’s seen it,” Biden said.

The Kremlin categorically denied any accusations related to the murder of civilians, including in Bucha, where it said the graves and corpses had been staged by Ukraine to tarnish Russia. — Reuters