The US has offered that Turkey give its Russian-purchased S-400 air defense systems to Ukraine, but Ankara has rejected the idea as threatening its national independence, Turkish Foreign Minister Mevlut Cavusoglu said on Sunday.

Read more: India: Russia begun delivering S-400 missile defense system

Turkey was kicked out of the F-35 program in April 2021 after purchasing Russia's S-400 air defense systems. Later that year, Turkish President Recep Tayyip Erdogan stated that Washington had given Ankara F-16 planes, which were one generation behind the F-35s. However, the agreement must be approved by the US Congress, and many congressmen are highly opposed to the effort.

"There were several proposals from the US considering S-400s. We were told, 'Give us control.' This is a proposal that affects our independence. Where is our independence then?... We were even offered sending them [S-400s] to Ukraine, but we said we could not," Cavusoglu said speaking to Turkish broadcaster Haberturk. 
 
In 2017, Turkey inked a $2.5 billion contract with Russia to purchase S-400 air defense missiles, with an option to purchase another batch. The deal called for the first batch to be a straight purchase, with the second regiment to include technology sharing, collaborative manufacture, and software integration.

According to Turkish media, in 2019, Turkey received the first regiment of Russia's S-400 air defense missile systems. Moscow said in August 2022 that the shipment of the second regiment of S-400 anti-aircraft missile systems was also started. However, the delivery was postponed in March 2023 owing to Ankara's disagreement with a clause limiting the equipment's sale to third nations.

In December 2020, the US imposed sanctions on Turkey's Defense Industry Directorate, its chief, and other employees, following the country's acquisition of the first batch of S-400s. 

Cavusoglu said on April 3 that Ankara is expecting a "positive outcome concerning its bid to purchase F-16 fighter jets from the US, once US President Joe Biden solves the remaining obstacles that lay ahead of the sale.

The sale was expected to replace Turkey's contributions to the F-35 program.

"In fact, there is no such thing as complete blocking. We know that the [Biden] administration is making sincere efforts. They are determined to provide Turkey with F-16 or kits required to modernize the existing Turkish aircraft. There are those who are against it in the Congress, but we know, that the administration is making effort regarding those who are against. We also expect positive outcome," Cavusoglu said, as quoted by Turkish broadcaster TRT Haber. 

The diplomat added that the Biden administration has to first convince the US Congress and get its approval to greenlight the deal, a deal he says can only be reached through dialogue with US lawmakers.