Turkey's defense minister said it was preparing for potential U.S. sanctions over its purchase of Russian S-400 missile defense systems, even while he said there was some improvement in talks with the United States over buying F-35 fighter jets.
Turkey and the United States have been at odds on several fronts including Ankara's decision to buy the S-400s, which cannot be integrated into NATO systems.
Washington says it would jeopardize Turkey's role in building Lockheed Martin F-35 fighter jets, which it says would be compromised by S-400s.
Related: Turkey is fulfilling its responsibilities in the F-35 and agreed over S-400
In trying to persuade Turkey to give up the Russian missiles, the United States has offered to sell its rival Raytheon Co. Patriot missile defense systems, which Akar said Ankara was evaluating.
He said Turkish and U.S. officials were working on price, technology transfer and joint production issues on the latest U.S. offer in late March.