"The agreement on the acquisition of Russian S-400 air defense systems by Ankara is an important step in terms of developing cooperation between Turkey and Russia. Russian systems are very important... Deliveries are an internal affair of Turkey. This is our decision. We made this decision, we agreed with Russia. From the NATO point of view, this step does not carry any negative meaning," Erdogan said at a meeting with Turkish youth in Trabzon, Sputnik reported.
Russia and Turkey signed a contract for the supply of four S-400 air defense system battalions worth $2.5 billion in 2017, deliveries to the Turkish side were made in the summer and fall of 2019.
The contract included an option for another regimental set. At the end of August 2021, Erdogan said that he had no doubts about buying a second S-400 regiment from Russia.
Turkey caused a rift with the US, its NATO ally, when it bought Russian-made S-400 air defense systems. The United States cancelled the sale of F-35 jets to Turkey in 2019 over claims that it could leak military secrets to Russia. The Kremlin and Ankara have both strongly rejected such a possibility.