Turkey won’t be allowed back to the F-35 stealth fighter jet program, U.S. House Armed Services Committee (HASC) Chairperson Adam Smith said Wednesday as Ankara maintains that it will not accept Sweden and Finland’s NATO applications unless they take concrete steps to meet the country’s demands regarding terrorist organizations.

"Turkey’s not coming back into the F-35 program," Smith, told reporters at an event hosted by the Defense Writers Group.

Turkey initially joined the U.S.-led multinational fifth-generation F-35 fighter jet program with a $1.4 billion (TL 24.2 billion) investment but was removed by Washington in 2019 after it acquired S-400 missile defense systems from Russia. Ankara had ordered more than 100 F-35 jets, made by Lockheed Martin, while its defense industry has been a prominent player in the development and manufacturing of fighter jets.

Washington argues that the S-400 air missile systems acquired by Turkey could be used by Russia to covertly obtain classified details on the F-35 jets and that they are incompatible with NATO systems. Turkey, which purchased the missile system after initially requesting Patriots from the U.S.– which it did not get – however, insists that the S-400 would not be integrated into NATO systems and would not pose a threat to the alliance.

"It’s not about, you know, punishing Turkey for buying Russian weapons systems. It’s about not having the S-400 in the same place as the F-35 and the potential loss of critical information there to the Russians on that," Smith further said.

"I think the way it ends is basically get some sort of weapons to them. It probably won’t be the F-35... And I don’t know what Europe does or does not sell Turkey," Smith said. "I think I see that’s probably the way this ends."

Sweden and Finland formally applied to join NATO on May 18, a decision spurred by Russia's war on Ukraine, which began on Feb. 24.

But Turkey, a longstanding member of the alliance, has voiced objections to their membership bids, criticizing the countries for tolerating and even supporting terrorist groups such as the PKK and the Gülenist Terrorist Group (FETÖ).

Previously, media reports citing senior Turkish officials who did not reveal their names, said Ankara has set certain conditions to support the two Nordic countries’ NATO bids, including the lifting of arms embargoes, a return to the F-35 program and the recognition of the PKK as a "terrorist organization" by the two countries.

Most recently, Foreign Minister Mevlüt Çavuşoğlu said that the documents sent regarding Sweden and Finland's NATO bids do not fulfill the Turkish government's expectations.

The top Turkish diplomat said Finland and Sweden's responses did not address Turkey's concerns and that Ankara has briefed Stockholm, Helsinki and NATO about the shortcomings.