Turkey received its first Russian S-400 missile system delivery on Friday, the defence ministry said, despite repeated warnings from its North Atlantic Treaty Organisation ally United States against the purchase.
Russian Federation began the delivery of an advanced missile defence system to Turkey it has been reported, a move likely to trigger USA sanctions against a North Atlantic Treaty Organisation ally and drive a wedge into the heart of the military alliance.
Russia's Federal Service for Military-Technical Cooperation confirmed it had started delivering the S-400 to Turkey and that the deliveries would continue as per an agreed schedule, the RIA news agency reported.
A Russian Air Force AN-124 cargo jet delivered the S-400 consignment to the Murted Air Base outside the capital Ankara.
But President Trump has been publicly supportive of Turkish President Recep Tayyip Erdogan and last month expressed sympathy for Erdogan's decision to purchase the S-400s.
Turkey says the system is a strategic defence requirement, particularly to secure its southern borders with Syria and Iraq.
The deal with Russian Federation has also raised concerns in Western circles that Turkey is drifting closer to Moscow's sphere of influence.
But Trump has not ruled out sanctions and Turkey could face expulsion from the F-35 programme under any punitive measures.
However, US defence officials have said they do not want the F-35 jets to be near S-400 systems - because they fear Russian technicians will be able to access the F-35's vulnerabilities.
"We've always said regarding the S400s that it's an agreement that has been finalized and the process continues to progress", Turkish Foreign Minister Mevlut Cavusoglu told reporters. Last week U.S. officials said the administration still planned to impose sanctions on Turkey.
Turkey has refused to bow to USA pressure, insisting that choosing which defence equipment to purchase is a matter of national sovereignty.
The U.S. has already stopped training Turkish pilots on the F-35, and given Ankara until the end of July to get its personnel out of the U.S.
The Murted base was formerly known as Akinci Air Base and was used by putschist soldiers in the failed 2016 coup.
Turkey maintains that it has fulfilled all of its financial obligations concerning the F-35 programme and can not be excluded from the project. The S-400 system can engage targets at a distance of 400 km and at an altitude of up to 35 km. Turkish media reports have said it could take until October for the system to be fully operational.