Russia accused the U.S.-led coalition of "complicity with terrorism" on Tuesday after an American warplane downed a drone operated by pro-regime forces in southern Syria.
"In Syria this type of strike is akin to complicity with terrorism," Russia's deputy foreign minister Sergei Ryabkov told the Interfax news agency.
The Iranian-made drone was downed Tuesday, just days after a U.S. warplane shot down an Assad regime fighter jet in the country's north.
Following the fighter jet's downing, Moscow suspended an incident hotline intended to prevent confrontations in Syria's crowded air space, and warned it could consider U.S.-led coalition planes "targets".
In Tuesday's incident, the U.S.-led coalition said an F-15E Strike Eagle jet destroyed an armed Shahed-129 drone in the early hours of the morning as it neared the Al-Tanaf base along Syria's eastern border.
"It displayed hostile intent and advanced on Coalition forces," the statement said.