Russia and the United States' top diplomats spoke to each other face-to-face on Thursday for the first time since Moscow's invasion of Ukraine on the sidelines of a Group of 20 meeting where ministers traded blame over the conflict.

U.S. Secretary of State Antony Blinken told Russian Foreign Minister Sergey Lavrov to end the war and urged Moscow to reverse its suspension of the New START nuclear treaty, a senior U.S. official said.

The Russian foreign ministry said Lavrov and Blinken spoke "on the move" for less than 10 minutes at the end of the closed-door session, and did not engage in any negotiations, Russian news agencies reported.