Turkey may call off Russia missile purchase - US Air Force chief

The chief of the US Air Force says it is still "possible" that Turkey will decide against purchasing a Russian missile-defense system, a deal that has angered Washington and many NATO allies.

Asked if Ankara may ultimately change its mind about acquiring the S-400 missile system, Air Force Secretary Heather Wilson said on May 16 that "it's possible."

"The diplomats are continuing the work on that," she said, reiterating the viewpoint that the Russian missile system is "incompatible with having the F-35 ."

The United States has demanded that Ankara call off the deal to purchase the Russian missile system, and NATO allies have also expressed concerns about the potential threat to US-made F-35 fighter jets.

Turkey, as a NATO member, is participating in the production of the fighter jet for use by alliance militaries and has plans itself to purchase 100 of the jets.

But U.S. officials have warned that Turkey's participation in F-35 production work and its planned purchase of the warplanes could be canceled if Ankara goes through with the Russian deal.