Story highlights The top diplomats for the U.S., Russia meet and say they want a negotiated peace in Syria

Russia has carried out airstrikes in support of a Syrian army advance on Aleppo

A top U.S. official accused Russia of helping ISIS with these strikes, by drawing other rebels to Aleppo

Moscow (CNN) As battles continue to rage around the embattled Syrian city of Aleppo, so too does the war of words among two far-away countries involved in the fight -- Russia and the United States.

The defense ministry for Russia, which has been lambasted for its own airstrikes in support of a Syrian government ground offensive around Aleppo, turned the tables Thursday with an accusation against the United States.

Ministry spokesman Igor Konashenkov said no Russian warplanes were within 12.5 miles (20 kilometers) of Aleppo on Wednesday, but members of the American-led anti-ISIS coalition were.

"Yesterday, ... two A-10 attack aircraft of the U.S. Air Force entered Syrian airspace from ... Turkey and, reaching Aleppo by the shortest path, made strikes against objects in the city," Konashenkov said.

Two U.S. officials, though, denied that any coalition aircraft were near Aleppo on Wednesday.