U.S. Secretary of State Antony Blinken claimed on Tuesday that Russia waged a "deliberate campaign" to commit atrocities in the Ukrainian town of Bucha.

"What we've seen in Bucha is not the random act of a rogue unit," Blinken told reporters before departing for Brussels for a NATO foreign ministers' meeting.

The Russian defense ministry on Sunday denied allegations of massacres committed in Bucha, calling them "another provocation" by Kyiv.