Turkey is facing mounting difficulties in its effort secure new Lockheed Martin F-16 fighters.

Twenty-nine US senators signed on to a 2 February letter declaring their opposition to the sale of the multi-role fighters to Turkey. The legislators cite Ankara’s opposition – championed by President Recep Tayyip Erdogan – to Nordic states Finland and Sweden joining the NATO military alliance.

F-16 ANG

Source: New Jersey Air National Guard

Turkey is pursuing a deal with Washington for 40 Lockheed Martin F-16s, plus additional kits to upgrade the Turkish air force’s existing fleet

“We write with concern about… continued delays ratifying the accession protocols for Sweden and Finland,” the senators say. “Congress cannot consider future support for Turkey, including the sale of F-16 fighter jets, until Turkey completes ratification of the accession protocols.”

The bi-partisan group represents nearly one-third of the 100-member US Senate, including several members of the influential committees overseeing the armed forces and foreign relations. New Jersey Democrat Bob Menendez, chair of the Senate Foreign Relations Committee, separately said he opposes Turkey’s request over Erdogan’s policy record.

Per the NATO charter, all existing members must unanimously approve a new applicant’s request to join the mutual defence bloc. Finland and Sweden sought to join the alliance in 2022 after Russia invaded Ukraine.

Turkey has opposed the two countries’ accession on the grounds they have supported the Kurdistan Workers Party – a Turkey-based militant group designated as a terrorist organisation by the USA and EU.

However, that opposition may cost Ankara its new fighters.

Under the US government’s Foreign Military Sales (FMS) process, the export of high-value or technologically sensitive weapons requires approval from both the US Department of State and Congress.

Turkey is seeking to acquire 40 of the single-engined fighters from the USA, as well as kits to modernise 79 of the Turkish air force’s existing F-16s, in a deal reportedly worth $20 billion. Ankara submitted an official FMS request in 2021.

The country currently operates 243 F-16C/Ds, according to Cirium fleets data.

The US Department of State recently concluded its preliminary analysis on the geopolitical implications of the F-16 sale and began a so-called informal review with select members of Congress in January.

A Department of State official who requested anonymity told FlightGlobal at the time the administration would use the discussions to gauge the level of support in Congress for the proposed arms sale. If Congress appears likely to approve the deal, the department will formally refer the deal to lawmakers for their authorisation.

That now appears unlikely, unless Ankara makes a sudden reversal on its NATO objections.

Although the 29 senators describe Turkey as “a valuable NATO ally”, the bi-partisan group is presenting a united front in opposing the F-16 sale until Erdogan chances tack.

Finland and Sweden, the senators note, “have worked to implement concerns” outlined by Turkey in a 2022 memorandum between the three countries meant to resolve the impasse.

“It is clear that both Sweden and Finland are making full and good faith efforts to meet the conditions for NATO membership that Turkey has asked,” the senators say. “Despite this evident progress, Turkey has not ratified the accession protocols for Sweden and Finland and has been unwilling to commit to a time line for consideration of ratification of the protocols.”

Notably, US President Joe Biden signalled his support for the F-16 sale at the time that memorandum was signed.

“We should sell them the F-16 jets and modernise those jets as well,” Biden said at a 2022 NATO summit in Madrid.

While currently opposing the deal, the senators are leaving open the possibility of reversing their stance in the future.

“Once the NATO accession protocols are ratified by Turkey, Congress can consider the sale of F-16 fighter jets,” the group says. “A failure to do so, however, would call into question this pending sale.”

Turkey is separately seeking to secure a small number Lockheed F-35 stealth fighters, which had been built for the country before Washington removed it from the multi-national programme in 2019 over Anakra’s purchase of a Russian air defence system.