Russia said on Sunday it had reached an agreement with the United States on the need to improve coordination between their military operations in Syria, where they are backing opposing sides of a civil war and launching air strikes.
Moscow's intervention on the side of President Bashar al-Assad, alongside Western backing for rebel groups and attacks on Islamic States targets, has raised the risk of a wider international confrontation in the war.
Russia's defense ministry said military officials from both countries had agreed on the need to improve coordination during a video conference. There was no immediate confirmation from Washington.
The announcement came a day after The Pentagon said it had questioned Moscow over Russian air strikes conducted against U.S.-backed Syrian opposition forces last week, saying Moscow had failed to heed U.S. warnings.
Smoke and flame rise after what fighters of the Syria Democratic Forces (SDF) said were U.S.-led air strikes on the mills of Manbij where Islamic State militants are positioned, in Aleppo Governorate, Syria June 16, 2016.
Russian Defence Ministry spokesman Igor Konashenkov dismissed the allegation, saying the Russian strikes hit about 300 km (190 miles) away from territory where the United States had said opposition forces were operating.
He said Russia had notified the U.S.-led coalition about the targets it was planning to strike.
"The Russian defense ministry for the past few months has been proposing to its American colleagues to draw a unified map, which would containing information about the location of the forces which were active in Syria. However, no material progress has been made on this issue," Konashenkov said.
Russia, which has been bombing opposition-held areas, is blamed by the opposition and rights activists for causing hundreds of civilian deaths and targeting hospitals, schools and infrastructure in what they say are indiscriminate attacks.
Moscow has repeatedly dismissed the allegations.