By deciding to bypass Congressional objections to the sale of F110 engines for the Turkish KAAN fighter jet, Donald Trump is attempting to placate Recep Tayyip Erdogan and remove one of the many burdens weighing on US–Turkish relations just days before arriving in the Turkish capital to attend a difficult and pivotal NATO Summit for the alliance’s future.

A summit taking place in a very heavy climate caused by the contradictory choices of President Trump, resulting in an at least cautious and cold, if not hostile, atmosphere among European and Canadian leaders toward the US president, who in Ankara will find a warm welcome only from his “friend” Erdogan.

The US president hastened on Wednesday to announce some kind of “gift” to the Turkish president, and as immediately became known through leaks confirmed by American officials, this appears to be the bypassing of obstacles raised in Congress, with Congressman Gregory Meeks playing a leading role, regarding the sale of F110 engines to Turkey.

This is certainly an important gesture toward Ankara, but it does not change the balance of power, as the sale of the engines does not automatically mean Turkey’s re-entry into the F-35 program, which continues to be blocked by sanctions imposed under the CAATSA legislation, nor does it grant automatic and unrestricted access to every US defense system.

No surprise

For Athens, the possibility of selling F110 engines to Turkey was not a surprise and was among the scenarios being considered by the Ministry of Foreign Affairs. It was considered certain that Trump wished to make a goodwill gesture toward Turkey, believing that Erdogan had aligned with his policies both on Ukraine and on Iran.

For Athens, what remains important is that Greece is already in the process of acquiring F-35 aircraft, which, combined with the Rafale jets already integrated into the Hellenic Air Force, provide significant air superiority. At the same time, Greek–American relations have acquired strategic depth both through the upgrade of the Souda Bay base and the provision of additional military facilities to US Armed Forces, as well as in the energy sector, with Greece emerging as a critical hub for the transport of American LNG to the Balkans and Eastern Europe.

The process in the United States

Military aircraft engines are considered defense material and require an export license (ITAR/EAR) from the US government. Approval is not automatic and is examined on a case-by-case basis. For major arms sales, Congress has the right to review and exert pressure, and in recent years several members of the House and Senate have linked approval of arms transfers to Turkey with issues such as the possession of Russian S-400 missile system systems, overflights above Greek islands, tensions in the Eastern Mediterranean, and Ankara’s policy in Syria.

The approval process for arms sales follows a specific procedure after Congress is notified of a proposed sale. In the informal review stage, members of Congress can place a “hold” on the process. In the formal notification stage, the government informs Congress and a 15- or 30-day review period begins.

A hold has no legal force but is a political practice. If the White House decides to proceed, it can simply ignore and bypass it. Even after formal notification, blocking the sale would require both the House of Representatives and the Senate to pass a joint resolution of disapproval. If the president vetoes it, a two-thirds majority in both chambers is required to override the veto. In practice, therefore, if a president decides to support a sale, Congress has very limited ability to stop it.

Democratic initiative to block the F-35s

On Sunday, however, it became known that Democratic Congresswoman from Nevada Dina Titus has taken an initiative in Congress with a letter currently collecting signatures, calling on House leadership to be prepared to use its legal powers to prevent any decision to reintegrate Turkey into the F-35 program, unless the issue of Russian S-400 missile system systems and CAATSA sanctions is first resolved.

The legal avenues available to Congress are defined in the Arms Export Control Act, which gives lawmakers the ability to attempt to block a transaction through a joint resolution of disapproval. The “joint resolution of disapproval” is the official legislative tool available after the government formally notifies Congress of a proposed sale.

The letter is to be sent to House Republican leader Steve Scalise and Democratic leader Hakeem Jeffries. It states that the Trump administration cannot bypass obligations under US law while Turkey continues to possess the Russian S-400 air defense system.

The authors of the letter also cite Vice President JD Vance, who said that an official review process is already underway on how a potential sale could legally proceed. As noted in the text, Vance stated that “Pete Hegseth and the entire team are currently examining the issue.”

The letter also recalls that in December 2020, the State Department of Trump’s first administration imposed sanctions on Turkey’s Presidency of Defense Industries under Section 231 of CAATSA, the law on Countering America’s Adversaries Through Sanctions Act. That decision, it notes, has not been revoked and remains in force.

The legal argument of the letter is that Turkey’s purchase of the S-400 constituted a significant transaction with an entity acting on behalf of Russia’s defense or intelligence sector. Lawmakers emphasize that there is no publicly available evidence that Turkey has removed the system, decommissioned it, or addressed the underlying cause of the sanctions.

Beyond CAATSA sanctions, the letter also cites the National Defense Authorization Act (Pentagon budget) for fiscal year 2020, which prohibits transferring F-35s to Turkey unless Ankara no longer possesses the S-400 system, provides assurances it will not seek to acquire it again, and confirms it has not accepted additional deliveries related to S-400s or any other system that could endanger US defense systems.

In the same context, lawmakers refer to a hearing of the House Foreign Affairs Committee on June 3, 2026, during which, as they note, Secretary of State Marco Rubio acknowledged that the administration is legally bound to maintain sanctions against Turkey and cannot reintegrate Ankara into the F-35 program.

With this initiative, Dina Titus seeks early Congressional mobilization against a possible Trump administration attempt to reopen the path for Turkey in the F-35 program. The message of the letter is that any such move cannot be seen only as a defense policy issue, but also as a matter of compliance with binding US legislation.

What it means for Turkey

For Turkey, such a decision regarding engines for the KAAN fighter jets is important for both political and substantive reasons. First, it would send a message that US–Turkish relations are thawing in the defense procurement sphere, removing a significant burden that has negatively affected bilateral ties. Practically, Turkey also solves a major problem, as its largest and most ambitious defense industry program—the KAAN fighter aircraft—can proceed to the first phase of production.

Turkey needs approximately 80 F110 engines worth $700 million for KAAN prototypes, flight tests, and early production batches, while Tusas Engine Industries (TEI) is developing the indigenous TF35000 engine, which is not expected to be ready until the mid-2030s. By securing American engines, Turkey gains a major advantage, as the KAAN program gains a stable timeline, reduces the risk of delays, and increases its credibility toward potential future customers.

Message to Israel

The geopolitical timing also matters. At a time when clouds have appeared in Trump’s relations with Israel, this gesture toward Turkey sends signals across the entire region and suggests that Washington seeks to keep Ankara as an important strategic partner within the NATO framework.

The decision comes just before the Alliance Summit, offering an important political card to Erdogan, who will seek to present the US president’s gesture as recognition of Turkey’s power and geopolitical weight both diplomatically and militarily.