The US Senate Armed Services Commission intends to block the sale of the # F-35 fighter bombers to #Turkey and remove Ankara from the #Lockheed Martin program, should the NATO ally continue its plan to purchase the system. Russian missile defense # S-400. The $ 2020 billion 750 National Defense Authorization Commission draft, unveiled on May 23, prohibits the sale of Lockheed Martin's F-35 Lightning II to Ankara if it proceeds with the purchase of the Russian air defense system. .

In recent months, Ankara has reiterated its intention to purchase the S-400, which US officials fear will allow Moscow to gather crucial information on the vulnerability of the F-35s, should Washington allow Turkey to have fighter-bombers. The United States has lobbied Turkey to buy #Raytheon's US-made Patriot missile defense system instead. According to press reports, Turkey will have to decide within two weeks whether to preserve the agreement with the United States on the purchase of the F-35 fighter-bombers, or risk sanctions by proceeding with the purchase of the Russian system. By the end of the first week of June, Turkey will have to cancel the Russian deal and buy the #Patriot missile defense system.

Another problem where Ankara no longer participates in the F-35 program is the lack, in the production chain, of some parts of the aircraft that should have been built in Turkey. This would create a delay in the entire production of about 2-3 months. A delay estimated by Pentagon experts that is not, however, confirmed by Lockeed-Martin's assessments.