The images shocked the world, but Ukrainian officials said it was only the beginning of the civilian murders the Russian retreat would reveal.

Iryna Venediktova, the prosecutor general, said the atrocities in Borodyanka were likely to overshadow those in Bucha and that Russia had “committed crimes against humanity”. She said: “In terms of human casualties, the worst situation is in Borodyanka. There’s a lot to process.”

In Mariupol, a once-bustling city of half a million people, Vadym Boichenko, the mayor, said almost every building had been destroyed.

“The horrors that we’ve seen in Bucha are just the tip of the iceberg of the crimes committed by the Russian army in the territory of Ukraine so far,” he said. “And I can tell you without an exaggeration, but with great sorrow, that the situation in Mariupol is much worse.”

Thousands of people have died, many of them civilians, and millions have had to flee from their homes since Vladimir Putin launched his invasion on Feb 24.

Mr Zelensky also blamed European leaders for encouraging Russian aggression with policies of “appeasement” towards the Kremlin after it annexed Crimea in 2014.

“I think that they need to come here and see what flirting with the Russian Federation amounts to,” he said on his visit to Bucha.