The Russian Defense Ministry said it is now treating any coalition aircraft flying west of the Euphrates as targets following the downing of a Syrian jet, Daily Mail reported.
Russia said it was suspending coordination with the US involving 'de-confliction zones' after a US Navy F/A-18E Super Hornet shot down a Syrian Air Force SU-22.
A communication line between Washington and Moscow that was intended to help coordinate flights to avoid midair collisions has also been shut down.
Russia said that the US did not use that line prior to shooting down the SU-22.
Russia has been providing air cover for Syrian President Bashar al-Assad's troops since 2015 and have deployed its advance S-400 Growler air defense system in the Latakia Airbase on the Syrian coast.
The Growler has a range of 250 miles and can hit targets up to an altitude of 90,000 feet.
The Russian Defense Ministry said in a statement that it was suspending the deal after the US military confirmed that it downed a Syrian air force fighter jet on Sunday after it dropped bombs near US partner forces.
“The shooting down of a Syrian Air Force jet in Syria's airspace is a cynical violation of Syria’s sovereignty,” the ministry said.
“The US repeated combat operations under the guise of combating terrorism against the legitimate armed forces of a UN member-country are a flagrant violation of international law and an actual military aggression against the Syrian Arab Republic.”
The ministry said it views the incident as Washington's “deliberate failure to make good on its commitments” under the de-confliction deal.
The Pentagon admitted it shot down the Syrian near Ja'Din, south of Tabqa on Sunday afternoon.
Russia's Deputy Foreign Minister Sergei Ryabkov on Monday condemned the US for the strike, describing it as an act of aggression.
“This strike has to be seen as a continuation of America's line to disregard the norms of international law,” Ryabkov told journalists in Moscow. “What is this if not an act of aggression?”