TEL AVIV – After the U.S. announced last month that it would not sell Turkey F-35s due to Ankara’s procurement of the Russian-made S-400 missile defense system, Turkish authorities are now considering buying Russian Su-35 fighter jets, a Turkish daily reported Sunday.

According to Yeni Safak, the country’s Presidency of Defense Industries (SSB), Turkish Air Force Command and other relevant authorities have been asked to investigate the possibility of purchasing the Russian jets.

Turkish officials have yet to comment on the report.

According to Russian news site Sputnik, Russia’s state-controlled arms agency Rosoboronexport offered to sell Su-35 fighters to Ankara.

The U.S. stopped Turkey’s F-35 program due to the belief that the country’s purchase of the Russian missile defense system risks the security of NATO members and constitutes a clear violation of a 2017 law threatening sanctions for any purchase of sophisticated Russian technology — the Countering Russian Influence in Europe and Eurasia Act of 2017.

The White House at the time said, “The F-35 cannot coexist with a Russian intelligence collection platform that will be used to learn about its advanced capabilities.”

Russia’s S-400 is considered one of the most advanced air-defense systems in the world.

At the time of the purchase, President Donald Trump blamed the Obama administration for never reaching a deal to sell a comparable American missile defense system to Turkey.

“Because they have a system of missiles that’s made in Russia, they’re now prohibited from buying over 100 planes,” Trump said of Turkey during a Cabinet meeting. “I would say that (F-35 manufacturer) Lockheed isn’t exactly happy. That’s a lot of jobs. And frankly I’ve always had a very good relationship” with Turkish President Recep Tayyip Erdoğan.

Trump said the decision to ban F-35 sales was one he was making reluctantly, as the F-35 is the world’s largest defense program and has already generated $12.9 billion worth of orders.

“We are now telling Turkey that because you have really been forced to buy another missile system, we’re not going to sell you the F-35 fighter jets,” the president said. “It’s a very tough situation that they’re in and it’s a very tough situation that we’ve been placed in, the United States. With all of that being said, we’re working through it, we’ll see what happens. But it’s not really fair.”

“Because of the fact he bought a Russian missile, we’re not allowed to sell him billions of dollars worth of aircraft. It’s not a fair situation,” Trump added.

Speaking to Turkish ambassadors in Ankara last week, Erdogan slammed the U.S.’s accusation that the purchase of the S-400s put Turkey’s commitment to NATO into question.

“There is no concrete evidence showing the S-400s will harm the F-35s or NATO, nobody should deceive each other. Many NATO member states have purchased from Russia. We don’t see this being turned into a crisis,” Erdogan said, according to Reuters.