The US Department of State has reaffirmed that Turkey cannot rejoin the F-35 Joint Strike Fighter program unless it abandons its Russian-made S-400 air defense system, in a formal response to lawmakers urging continued sanctions on Ankara.
In response to Congressional pressure, the State Department reiterates U.S. policy that Turkey remains barred from the F-35 program based on its acquisition of the Russian S-400 system and that section 1245 of the 2020 National Defense Authorization Act remains in effect.
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In a letter sent on August 20 to Representative Chris Pappas and other members of Congress, the State Department said the US position “has not changed” and that Turkey’s possession of the S-400 remains incompatible with participation in the F-35 program. The letter, signed by Paul D. Guaglianone, senior official at the Bureau of Legislative Affairs, stressed that requirements for Turkey are well established under US law, including section 1245 of the 2020 National Defense Authorization Act.
“The Trump Administration is fully committed to protecting US defense and intelligence assets and complying with US law, including CAATSA,” the letter said, referring to the Countering America’s Adversaries Through Sanctions Act, under which Turkey was sanctioned following its 2019 purchase of the Russian system.
The correspondence followed an August 7 letter by a bipartisan group of 40 lawmakers, led by Representatives Pappas, Gus Bilirakis, Dina Titus and Nicole Malliotakis, who urged the administration to reject Turkey’s request to rejoin the program. They warned that readmitting Ankara without dismantling the S-400s would “jeopardize the integrity of F-35 systems” and risk exposing NATO military secrets to Moscow.
Advocacy organizations including the American Hellenic Institute, the Armenian National Committee of America, the American Jewish Committee and American Friends of Kurdistan backed the congressional effort. These groups have long criticized Turkey’s foreign policy and military actions in the region.
Turkey was removed from the F-35 program in 2019 after taking delivery of the Russian system, which Washington said compromised NATO technologies. Ankara has since lobbied for reinstatement, arguing that its expulsion was unfair. The issue has resurfaced amid reports of renewed contacts between Ankara and Washington on fighter jet cooperation.
While Turkey remains a NATO ally, its defense relationship with Russia has faced bipartisan criticism in Washington. Efforts to restrict arms sales to Ankara have gained momentum in recent years, with Pappas also leading campaigns to block F-16 upgrades to Turkey.
The State Department letter emphasized that Washington still seeks cooperation with Turkey on shared priorities but underscored that “disagreements must be resolved through dialogue” and that US law will continue to guide decisions on sanctions and arms sales.