Turkish President Recep Tayyip Erdogan is seeking US approval to produce key parts of Boeing and Lockheed Martin Corp. aircraft locally, as Ankara moves to finalize major defense deals with Washington. Erdogan aims to offset more than $10 billion in planned payments for American aircraft through local production agreements, according to Bloomberg, citing people familiar with the matter.

The plans, which remain confidential, require approval from US President Donald Trump, who is set to host Erdogan at the White House on Thursday. The meeting is seen as a critical moment for Turkey as it works to repair ties strained by Ankara’s purchase of the Russian S-400 missile defense system.

Turkey’s decision to acquire the Russian S-400 system led to sanctions under the Countering America’s Adversaries Through Sanctions Act (CAATSA) and its removal from the F-35 development program. Ankara has refused to abandon the system but hopes Trump will amend sanctions, opening the door to renewed purchases of US aircraft.

Resolving the dispute could revive Turkey’s suspended role in the F-35 program, including contracts worth an estimated $12 billion for Turkish companies producing fuselage parts and electronics.

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Prospects for F-35 and F-16 fighter jet purchases

Erdogan is pressing for US approval to buy 40 F-35A jets and 40 new F-16 Viper fighters, in addition to bombs, missiles, and spare engines. The US had earlier approved the F-16 sale after Turkey ratified Sweden’s NATO membership.

Ankara currently operates around 240 F-16s, the world’s second-largest fleet after the United States, and seeks to replace its aging F-4s.

Turkey initially planned to purchase 79 F-16 upgrade kits as part of a $23 billion modernization deal, but has shifted focus to acquiring new F-35s if sanctions are lifted.

Ankara has also requested US permission to assemble GE Aerospace F110 and F404 engines used in American fighter jets and in Turkey’s domestically developed Kaan warplane and Hurjet trainer aircraft. Approval could speed up US engine production while boosting Turkey’s growing defense sector.

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Some Turkish electronics firms are expected to continue providing critical software and components, while others may help navigate European Union restrictions on certain materials used in jet manufacturing.