The Russian foreign ministry on Monday criticised UN Secretary General Ban Ki-moon over his claim that Russian air strikes in Syria had undermined last week's peace talks to end the country's five-year war.
"We have always considered and continue to consider that comments from the chief administrator of a global organisation ... should remain impartial and objective," the ministry said in a statement.
Ban had "practically" accused Russia of leading to the collapse of the talks, it added.
"This is clearly not what happened."
UN envoy for Syria Staffan de Mistura last week suspended attempts to begin a dialogue between President Bashar al-Assad's regime and the opposition, as Russia pressed its bombing campaign in the war-torn country.
Ban told Britain's The Financial Times newspaper last week that "aerial bombing continued" when the talks began, making it "extremely difficult" for negotiations to take place.
Washington had also accused Moscow of being "partly" responsible for torpedoing the Geneva peace talks.
One day after the talks broke down, Russia's defence ministry said that air strikes had hit 875 "terrorist targets" in Syria since the start of the month.
The strikes backed a major offensive by Syrian government forces and pro-regime fighters in the northern Aleppo region, the defence ministry said.
Moscow launched a bombing campaign in Syria last year at Assad's request, saying it was targeting the Islamic State group and other militant organisations.
The West has accused Russia of targeting more moderate factions that oppose Assad's regime, and Syrian activists say the strikes have killed civilians, allegations Moscow dismisses as "absurd".
Russian Foreign Minister Sergei Lavrov said last week that Moscow would continue the bombing campaign until "terrorist organisations" in Syria are defeated.