Policy Alert: Why Congress Must Block Any F-35 Transfer to Turkey
September 25, 2025 Policy Alerts
Policy Alert: Why Congress Must Block Any F-35 Transfer to Turkey
Bottom Line Up Front
Congress has drawn a red line: Turkey cannot receive F-35 aircraft while it continues to possess the Russian S-400 air and missile defense system.Section 1245 of the FY 2020 National Defense Authorization Act (P.L. 116-92) makes this prohibition explicit and mandatory. The law requires the Secretaries of Defense and State to certify, in writing, 90 days before transferring any F-35 aircraft to Turkey, that Turkey has removed all S-400 equipment and personnel, pledged never to reacquire it, and not accepted any other Russian systems that could compromise the jet.
Turkey has not met a single one of these conditions. Yet Ankara is lobbying aggressively for readmission to the F-35 program, as Turkey’s president, Recep Tayyip Erdoğan, meets with President Trump today. Moving forward with such a transfer would not only violate U.S. law but also put America’s most advanced stealth technology at risk, endanger American and allied troops flying F-35s, undermine NATO cohesion, and betray U.S. allies in the Eastern Mediterranean. The F-35’s advanced technology is central to U.S. security and dominance in future conflicts with near-peer adversaries—it must be protected.
The analysis below breaks down the stakes of this issue and outlines concrete actions Congress can take to enforce the law and protect U.S. national security.
FDD Action Expert Analysis
“Turkey remains closely aligned with Russia, with strong ties between the defense industrial bases of both countries. Turkey is also one of the largest purchasers of Russian energy, which continues to give Putin huge leverage over Erdoğan. The U.S. cannot give the F-35 to Turkey without undermining the U.S. fleet of fighter aircraft and jeopardizing all other F-35 variants sold to our NATO allies specifically to prepare them to combat the Russian military threat. The U.S. has many other avenues to make Turkey a more capable partner within NATO without providing the F-35.”
– Tyler Stapleton, Senior Director of Government Affairs, FDD Action
Why It Matters
The law is clear, and Turkey remains out of compliance.
The Trump administration expelled Turkey from the F-35 programin 2019 and sanctioned it under the Countering America’s Adversaries Through Sanctions Act (CAATSA) after Ankara purchased Russia’s S-400 air and missile defense system despite repeated U.S. warnings.
Congress has consistently upheld bipartisan restrictions on Turkey’s access to the F-35. The statutory language in Section 1245 is not a guideline but a binding requirement: no certification, no transfer.
Unlike CAATSA sanctions, which allow for discretionary waivers, Section 1245 leaves no room for interpretation. As the State Department itself recently acknowledged, “the U.S. position on Turkey’s S-400s has not changed,” and the administration “is fully committed to complying with U.S. law.” Without the necessary certification, any sale or transfer of F-35 aircraft or related systems to Turkey would be a clear violation of the law.
The S-400 is not just another weapons system; it is a direct intelligence threat to the F-35.
Turkey’s decision to purchase and deploy the Russian-made S-400 in 2019 was a turning point in U.S.-Turkish defense relations. The system is designed to detect, track, and potentially exploit advanced stealth aircraft like the F-35.
Turkey’s possession of both the S-400 and the F-35 is so dangerous because the two systems operating in proximity or networking together could give Moscow valuable intelligence for shooting down F-35s flown by Americans and our allies. Erdoğan could either give the information to Moscow, or Russians in Turkey could obtain the information.
This risk is precisely why Turkey was expelled from the multinational F-35 consortium in 2019 and why it was sanctioned under CAATSA. Allowing Ankara back into the program now would undo years of hard-won security safeguards.
Rewarding Turkey would punish America’s most reliable allies.
In recent years, Greece, Cyprus, and Israel have proven themselves to be indispensable U.S. partners in the Eastern Mediterranean. Greece plays an important role in joint maritime security operations. Cyprus hosts a U.S.-funded training hub that enhances counterterrorism and cybersecurity cooperation. Israel continues to serve as America’s frontline partner in blunting Iran’s nuclear weapons program.
By contrast, Turkey has repeatedly violated Greek sovereignty, openly threatened Cyprus for purchasing air-defense systems, and even threatened to invade Israel last year. Handing Erdoğan the F-35 would not reward loyalty, but hostility and aggression.
President Erdoğan remains an unreliable NATO partner who plays both sides.
Analysts have noted that Erdoğan views U.S. fighter jets as political leverage rather than as tools of alliance defense. As FDD’s Sinan Ciddi and William Doran recently argued in the New York Post, Erdogan is seeking to “cash in” on U.S. goodwill while continuing to deepen ties with Moscow and Tehran.
Granting him F-35 access would effectively deliver a strategic gift to America’s adversaries. Erdoğan has spent years undermining NATO unity, threatening fellow allies, and cozying up to Russia, yet now wants to be rewarded with the very system designed to deter those adversaries.
Turkey remains closely aligned with global terrorism movements that undermine the NATO alliance.
Erdoğan has materially supported terror groups like Hamas, contradicting U.S. policy and endangering the security of the region. Since the 10/7 attacks on Israel, Erdoğan has praised the U.S.-designated terrorist group, improving ties with its leadership, and mourning the deaths of its leaders. This year, he marked the end of Ramadan with a prayer that Allah “destroy and devastate Zionist Israel” and for “mercy upon the martyrs” of Hamas and Palestinian Islamic Jihad, also a designated terrorist group.
Erdoğan has also supported terror groups in Syria, including several designated by the U.S. for supporting the Islamic State and Al-Qaeda. Turkey’s state sponsorship of terrorism undermines the NATO alliance and efforts to promote regional stability.
Turkey does not need the F-35 to defend itself.
Turkey, in recent weeks, has taken several actions that make the sale of F-35 aircraft to the country unnecessary. Turkey agreed to purchase 40 Eurofighter jets from the EU. These aircraft are more than capable of providing Turkey a formidable defense against Russian aircraft incursions and other aerial threats.
Turkey is also close to the introduction of the Kaan aircraft, which is a fifth generation fighter with capabilities similar to the F-35. This indigenously produced aircraft will give Turkey significant capability without the need for the U.S. to compromise its F-35 fleet.
What Congress Can Do
Congress should reaffirm that the law already blocks any F-35 transfer to Turkey.
A bipartisan statement from leadership or key committees would underscore that Sec. 1245 remains the controlling statute and cannot be bypassed without verifiable changes in Turkey’s actions.
Congress should double down on support for reliable allies.
Strengthening defense cooperation with Greece, Cyprus, and Israel, partners that actively bolster U.S. security interests, would send a clear signal that Washington rewards responsible partners, not aggressors.
Endorsed: The bipartisan American-Hellenic-Israeli Eastern Mediterranean Counterterrorism and Maritime Security Partnership Act of 2025 (H.R. 2510) deepens U.S. security cooperation with Greece, Cyprus, and Israel, while reaffirming congressional opposition to rewarding Ankara’s aggression with advanced U.S. weapons systems. By codifying support for reliable allies in the Eastern Mediterranean, H.R. 2510 advances Congress’s intent under Sec. 1245 of the FY20 NDAA and strengthens the legislative firewall against any transfer of F-35 aircraft to Turkey.
Congress should be ready to impose consequences if the law is skirted.
Any attempt to circumvent Sec. 1245, such as transferring F-35s to non-sanctioned Turkish entities, should trigger immediate legislative pushback, including new sanctions.
Congress needs the full picture on Turkey’s support for terrorism.
The intelligence community should provide Members of Congress and staff a regular assessment of Turkey’s support for terror groups such as Hamas and other entities in Syria that have been designated for terrorism. The assessment should include any Turkish financial institutions supplying funds to terror groups and any designated individuals residing in or transiting in or through Turkey.