S-400 missile defense system

Turkey has received the first batch of Russian S-400 air defense system components on Friday, the Turkish ministry of defense has announced.

“Turkey received the first batch of S-400 air defence systems components. The deliveries are sent to the Murted air base in Ankara province", the Turkish Defence Ministry said.

Russia and Turkey penned a $2.5 billion agreement on the sale of four battalion sets of S-400s to Turkey in late 2017.

The announcement by the ministry has come after the US Department of Defense threatened to remove Ankara from the Lockheed Martin F-35 program on July 10.

“The Department of Defense will remove Turkey from the F-35 joint strike fighter program if the nation accepts delivery of the Russian S-400 air defense system,” Katie Wheelbarger, the acting assistant secretary of defense for international security affairs, said, on Wednesday.

According to the Pentagon, the NATO alliance and nations partnering in developing and fielding the F-35 are unified in their opposition to Turkey fielding the Russian system.

The concern is that the S-400 could be used to gather data on the capabilities of the F-35, and that the information could end up in Russian hands, officials explained.

"We offered the opportunity to them to buy the Patriot [air defense system] numerous times in a more generous package than we've offered anybody else, and they did not sign up for it," Wheelbarger added.

Washington has also halted the training of Turkish pilots of the F-35 fighter jets in addition to threatening economic and other military sanctions against Ankara.