Turkish President Recep Tayyip Erdogan on July 26 reiterated that Turkey plans to start using the Russian S-400 missile-defense system in April.
"In the coming spring, God willing in April 2020, we will be able to start using this system," Erdogan told a gathering of his Justice and Development Party (AKP) in Ankara.
U.S. and NATO military officials have long opposed Turkey's purchase of the S-400 from Russia, saying it was not compatible with alliance military systems and would endanger new F-35 jets used by the West.
The United States says Russia will be able to glean sensitive technical knowledge about the F-35 if it is operated alongside the S-400.
Russia began delivering components of the S-400 system this month, and Washington reacted by kicking Turkey off its F-35 fighter jet program.
Erdogan also said Turkey would turn elsewhere for fighter jets if the United States will not sell it F-35s.
"You won't give the F-35? Very well, excuse me, but we will take measures in this regard and will turn towards others," Erdogan said.
"No threats or sanctions against Turkey, especially threats to remove [Turkey] from the F-35 project, will prevent Turkey from ensuring its security priorities."