Turkish President Tayyip Erdogan said on Saturday that the purchase of S-400 defense systems from Russia was a done deal, adding that Ankara would also jointly produce S-500 defense systems with Moscow.

Axar.az reports citing Reuters.

U.S. officials have called Turkey’s planned purchase of the S-400 missile defense system “deeply problematic,” saying it would risk Ankara’s partnership in the joint strike fighter F-35 program because it would compromise the jets, made by Lockheed Martin Corp.

However, Erdogan told a televised question and answer session with university students in Istanbul that Turkey had carried out technical work and found that such a problem did not exist.

“They (the U.S.) are passing the ball around in the midfield now, showing some reluctance. But sooner or later, we will receive the F-35s. (The U.S.) not delivering them is not an option.”