Turkey's Patriot process will be terminated if Ankara purchases Russia's S-400 missiles, said a top U.S. official on Thursday.
Russia and Turkey signed the contract on the S-400 air defense systems delivery in 2017. Installation of the S-400s in Turkey is expected to begin in October 2019.
The S-400 is Russia's most advanced long-range anti-aircraft missile system, with the ability to carry three types of missiles capable of destroying targets, including ballistic and cruise missiles.
In December, the U.S. State Department approved a possible foreign military sale of the Patriot air and missile defense system to Turkey for an estimated total of $3.5 billion.
According to the Defense Security Cooperation Agency, the department approved the sale of 80 Patriot MIM-104E Guidance Enhanced Missiles (GEM-T) missiles, 60 PAC-3 Missile Segment Enhancement (MSE) missiles and associated equipment.
Turkey had been trying to purchase the air defense system from the U.S., but the missiles have never been sold to Turkey when they were needed the most, according to the government.
Washington has complained that the Russian system is not compatible with weapons used by other NATO countries.
Separately, in a report in late November, the Pentagon warned that purchasing the S-400 system would have unavoidable negative consequences for U.S.-Turkey relations as well as Turkey's role in NATO.
Patriot missiles are used for defense purposes, mainly to shoot down incoming missiles and planes.
U.S. Syria withdrawal
Asked about the U.S.'s troop pullout from Syria, "The U.S. will withdraw, there is no doubt about that," he said.
