Previously, Turkey has repeatedly expressed its interest in the joint production of S-400. In April, Kremlin spokesman Dmitry Peskov specified that "there is and can be no talk" about the two countries’ joint production of S-400 systems. He, however, did not rule out that some components would be produced jointly.
"The S-400 deal is completed. Under the contract, the deliveries are to begin in July or, maybe, even earlier. Russia has offered us very good conditions. After that, we will talk about the S-500, including joint production [of these systems], as well as S-400," Erdogan said at a meeting with the youth, as broadcast by the NTV channel.
In December 2017, Moscow and Ankara signed a loan agreement for the delivery of S-400 systems. Since then, Turkish cooperation with Russia on S-400 deliveries has been extremely criticized by NATO and the United States, which cited security concerns and incompatibility of S-400s and NATO's air defence systems.
Washington has threatened Ankara with sanctions for its planned acquisition of S-400s and repeatedly said it may delay or cancel the process of selling the F-35 aircraft to Turkey, which is one of the participants in the US F-35 international program. Ankara, in turn, has said that purchase of these defensive weapons is its sovereign affair, ruling out the possibility of abandoning its plans.