Russian Federation says it will now treat all USA -led coalition planes in the air over Syria, west of the Euphrates, as targets after an American fighter jet for the first time in the six-year conflict shot down a Syrian military plane.
According to the Associated Press, the Pentagon's efforts to de-escalate following the strike do not appear to have been successful: "Russia says it will treat US-led coalition planes in Syria, west of the Euphrates, as targets after U.S. downed Syrian jet".
Those forces, which are aligned with the U.S.in the campaign against the Islamic State group, warned Syrian government troops to stop their attacks or face retaliation.
Just hours earlier, the USA had bombed Syrian government and allied troops inside a protected zone in that area and marked a sharp escalation in the skirmishes between the coalition and those pro-Syrian government forces there.
The United States has moved quickly to contain an escalation of the situation after the jet was downed on Sunday evening when regime forces targeted the US-backed Syrian Democratic Forces, an alliance of Arab and Kurdish fighters battling IS.
It also said the USA shootdown of a Syrian SU-22 fighter was a violation of a 2015 memorandum of understanding on prevention of aerial incidents in Syria and that Moscow had therefore suspended their cooperation with Washington under the memorandum.
Russia, which is flying its own air war in Syria to prop up President Bashar al-Assad, condemned the incident and said it had shut off a special "deconfliction" hotline with the USA military, though top officer General Joe Dunford later said the United States was seeking to re-establish the channel.
Since Monday, the Russian Ministry of Defense has suspended a memorandum of cooperation with the United States aimed at avoiding air incidents in Syria.
Dunford said Monday, June 19, 2017, that Washington and Moscow are in delicate discussions to tamp down tensions arising from the US shootdown of a Syrian fighter jet, which the Russians called a violation of a U.S.More news: Confederations Cup 2017: Late drama ensues as Mexico battle to hold Portugal
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Ryabkov asks: "What is this, if not an act of aggression?"
According to a statement from the Pentagon, pro-Syrian regime forces attacked the US -backed Syrian Democratic Forces-held town of Ja'Din, south of Tabqah in northern Syria, wounding a number of SDF fighters and driving the SDF from the town.
Government ally Iran also Sunday launched missiles from its territory against alleged IS positions in eastern Syria for the first time, in response to an IS-claimed attack in Tehran.
The two countries support opposing sides in Syria's civil war.
This weekend's fast-paced developments bring new urgency to easing escalating strains between Washington and Moscow, who are both fighting in Syria but with opposing objectives.
The actions of the US Air Force are in fact "military aggression" against Syria, the statement adds.
Moscow accused Washington of failing to honour the pact by not informing it of the decision to shoot down the Syrian plane despite Russian aircraft being airborne at the same time.
These incidents, however, are tactical, not part of any US strategy in Syria, analysts said. He said government forces began attacking the SDF on Saturday, using warplanes, artillery and tanks in areas that SDF had liberated from IS.