The first delivery of the Russian S-400 advanced long-range anti-aircraft missile system, also known as the SA-21 Growler, has arrived in Turkey.

The components of the first S-400 missile system battery of Turkey was delivered at Akıncı Air Base of Turkish Air Force at Ankara onboard an An-124-100 military transport aircraft of Russia Air Force’s 224th Flight Unit with RA-82038 register early morning today, according to military analyst Babak Taghvaee.

Later Turkey’s Defense Ministry confirmed the first parts of the S-400 Russian missile defense systems were delivered to Ankara.

The ministry said the first delivery of the S-400 air defense systems arrived on Friday at an air base near the capital, Ankara.

The United States has warned Turkey it will face economic sanctions if it goes ahead with the purchase of a Russian missile defense system. It has also said Turkey won’t be allowed to participate in the program to produce the high-tech F-35 fighter jets.

Turkey has refused to bow to U.S. pressure, insisting that choosing which equipment to purchase is a matter of national sovereignty.

News about Russian-Turkish talks on the delivery of the S-400 systems first came in November 2016. In September 2017, Erdogan announced that Ankara had signed a contract with Moscow on purchasing the S-400 systems and made an advance payment. Turkish Defense Minister Hulusi Akar said later that Ankara would begin the deployment of the S-400 systems in October 2019. Russia’s Rostec State Corporation Sergei Chemezov said in December 2017 that the deal was worth $2.5 bln.

#BREAKING: Half of the components of the first S-400 SAM battery of #Turkey was delivered at Akıncı Air Base of #Turkish Air Force at #Ankara onboard an An-124-100 of #Russia Air Force’s 224th Flight Unit with RA-82038 register early morning today. pic.twitter.com/Ypmq1RtumA

— Babak Taghvaee (@BabakTaghvaee) July 12, 2019

#BREAKING: #Turkish media (#Erdogan‘s Anadolu Agency) released video of the first S-400 SAM battery of #Turkey which were delivered by two #Russia Air Force’s An-124-100 transport airplanes, RA-82038 and RA-82013 from 224th Flight Unit at #Akinci AB, #Ankara few hours ago. pic.twitter.com/nT1HX7PKwV

— Babak Taghvaee (@BabakTaghvaee) July 12, 2019