June 19 (UPI) -- Russia said it is ending logistical military coordination with the United States and threatened to shoot down any aircraft west of the Euphrates River after the U.S. Navy shot down a Syrian regime jet.
The "deconfliction" communication agreement between Washington, D.C., and Moscow was previously established to avoid problematic encounters while aircraft operated above Syrian territory.
The U.S.-led international coalition fighting the Islamic State on Sunday said it shot down a Syrian regime fighter jet because it was attacking the U.S.-backed Syrian Democratic Forces militia near Tabqah. The SDF is leading the ground offensive in Syria to capture the Islamic State's stronghold of Raqqa.
Russia's Defense Ministry on Monday said it ended the agreement "preventing incidents and providing for safe flights during operations in Syria." The ministry also said it demands an investigation and report from the United States about its operation in which the jet was shot down.
"The shooting down of a Syrian air force jet in Syria's airspace is a cynical violation of Syria's sovereignty," the ministry said in a statement. "The U.S.' repeated combat operations under the guise of 'combating terrorism' against the legitimate armed forces of a U.N. member-state are a flagrant violation of international law, in addition to being actual military aggression against the Syrian Arab Republic."
The Russian ministry said any aircraft operating west of the Euphrates River will now be regarded by the Russian air force as legitimate targets, which will either be shot down or escorted out of the area.
"Any aircraft, including planes and drones of the international coalition, detected in the operation areas west of the Euphrates River by the Russian air forces will be followed by Russian ground-based air defense and air defense aircraft as air targets," the ministry said.
Russia said the United States shot down a Syrian regime jet fighter that was attacking Islamic State targets about 25 miles west of Raqqa. The ministry said the Syrian pilot ejected over territory controlled by the Islamic State, adding the pilot's condition is not known.