Russia warns U.S. after downing of Syrian warplane

Nation vows to target American aircraft flown west of Euphrates, suspends use of hotline

Russia ends use of hotline, threatens to target aircraft flown by the United States and its allies west of the Euphrates river.

WASHINGTON — Longrunning tensions between the United States and Russia erupted publicly on Monday as Moscow condemned the U.S. military’s downing of a Syrian warplane and threatened to target aircraft flown by the United States and its allies west of the Euphrates.

The Russians also said they had suspended their use of a hotline that the U.S. and Russian militaries used to avoid collisions of their aircraft in Syrian airspace.

The episode was the first time the United States has downed a Syrian plane since the civil war began there in 2011 and came after the SU-22 jet dropped bombs on Sunday near U.S.backed fighters combating the Islamic State.

It followed another major U.S. military action against the Syrian government: a cruise missile strike to punish a nerve gas attack that killed civilians in April.

The latest escalation comes as competing forces converge on ungoverned swaths of Syria amid the country’s six-year civil war. Syrian forces and Iranian-backed militias that support them are extending their reach east closer to U.S.-backed fighters, including forces that the Pentagon hopes will pursue the militants into the Euphrates River valley after they take the Islamic State’s self-declared capital of Raqqa. The collision of the disparate forces has, in effect, created a war within a war.

“The escalation of hostilities among the many factions that are operating in this region doesn’t help anybody,” Sean Spicer, the White House press secretary, told reporters on Monday.

President Donald Trump has allowed military commanders more say in conducting operations against the Islamic State, urging them to surround the militants in their strongholds and “annihilate” them.

Russia’s warnings could turn out to be posturing. The Russian military has threatened to halt its use of the hotline in the past — notably after Trump ordered April’s missile launch — only to continue and even expand its contacts with the U.S. military. But in the complicated and quickly unfolding situation in Syria, even bluster can risk an unintended showdown.

“Anytime we have multiple armed forces working in the same battle space without deconfliction, there is a dangerous risk of things spinning out of control,” said Douglas E. Lute, a retired three-star Army general who was the U.S. representative to NATO until January.

U.S. military officials rushed to de-escalate the situation, saying they hoped Russia could be persuaded to keep using the hotline.

“This is a delicate couple of hours,” Gen. Joseph F. Dunford Jr., chairman of the Joint Chiefs of Staff, said Monday.

He added that the United States would work both diplomatically and militarily “to reestablish de-confliction.”