Turkey will have to ditch the advanced S-400 air defense system bought from Russia for $2.5 billion as a first step in improving relations with the U.S. and NATO, Pentagon officials said Thursday.
"If Turkey wants to come back in the fold, the path forward is to get rid of the S-400," said Jonathan Hoffman, the Pentagon's chief spokesman.
The S-400 Triumf has been billed by Moscow as effective against the stealthy F-35 Joint Strike Fighter.
Turkey can't just "keep it in a warehouse and lock it up. They need to divest themselves of that weapons system," Hoffman said. "We have received no indication that they have reversed course and are seeking to go in a different direction."
Instead, Turkey has begun testing the system, said Rear Adm. William D. Byrne, Jr., vice director of the joint Staff, who joined Hoffman at the briefing.
"We're aware that there was some testing going on," Byrne said, but "we have no indication that it's employed in the field."
Turkish President Recep Tayyip Erdogan went ahead with the buy despite repeated warnings from the U.S. that the S-400 was incompatible with NATO systems and could pose a threat to F-35s.
The dispute with Washington intensified in October, when Turkey invaded northeastern Syria to create a safe zone along its border and push out members of the mostly-Kurdish Syrian Democratic Forces, who are allied with the U.S.
The invasion endangered about 25 U.S. Special Forces troops who had been running joint patrols with the Turks in northeastern Syria. Russia and Syrian troops have since pressed forward to fill the vacuum.
Hoffman urged Turkey to change course, saying Turkey would be "better off working with the U.S. and NATO than going in a different direction."
In response to the S-400 buy, the U.S. has barred Turkey from the purchase of F-35s. Turkey was also set to lose production work on parts for the F-35 in March, but the Trump administration has held off on imposing sanctions. Those sanctions would fall under the Countering America's Adversaries Through Sanctions Act (CAATSA) aimed at countries who do business with Russia's defense sector.
On Wednesday, Congress moved forward on invoking CAATSA when the Senate Foreign Relations Committee voted 13-4 to sanction Turkey.
Shortly after the Committee vote Wednesday, Turkish Foreign Minister Mevlüt Çavuşoğlu suggested Turkey could retaliate against sanctions by booting U.S. troops from Incirlik Air Base and Kurecik Radar Station in Turkey.
"Both Incirlik and Kurecik may come to our agenda ... [but] we don't want to talk about the bad scenario over assumptions," Cavusoglu said, according to Turkey's Anadolu news agency.
-- Richard Sisk can be reached at Richard.Sisk@Military.com.