Kyiv and the West say there is evidence - including images and witness testimony gathered by Reuters and other media organisations - that Russia committed war crimes in the Ukrainian town of Bucha.Â
Moscow denies the charge and has called the allegations a "monstrous forgery."
Lavrov said, without providing evidence, that Moscow believed the accusations were timed to wreck the negotiating process after what he described as progress when Ukrainian and Russian representatives met in Turkey last week.
"We are inclined to think the reason is a desire to find a pretext to break off the negotiations that are being conducted," he said in a video issued by the Russian foreign ministry.
In a sign of the remaining gulf between the two sides after nearly six weeks of war, Lavrov said Moscow was still insisting on the demilitarisation and "denazification" of Ukraine and protection for Russian-speakers there, but Kyiv was denying that these were real problems.
Ukraine and Western governments say these demands, presented by President Vladimir Putin at the start of Russia's invasion, were false pretexts for an illegal assault on a democratic country.
Lavrov said, again without providing evidence, that Ukraine had "tried to break off the negotiating process altogether" after Western media published the war crimes allegations.
