"Because of delays of deliveries of the weapons that we are expecting from the United States, Turkey had to look for alternative variants," Foreign Minister Mevlut Cavusoglu said at a meeting of the parliament’s budget committee, as quoted by the Hurriyet newspaper,
Relations between Turkey and the United States have further deteriorated as a result of the arrest of Metin Topuz, an employee at the US Consulate General in Istanbul, for alleged links to the movement of Islamic cleric Fethullah Gulen, who is accused by Ankara of masterminding the 2016 failed coup attempt and is residing in the US.
Deal on S-400 Supplies
Despite a strong opposition from NATO members, Moscow and Ankara reached an agreement on the delivery of S-400 systems to Turkey on September 12, 2017. Two weeks later, Russian presidential aide Vladimir Kozhin confirmed that Turkey had made an up-front payment for the air defense systems, adding that the delivery is scheduled for 2019.
Speaking about the deal, Prime Minister Binali Yildirim said that Ankara had no other choice because due to the lack of modern air defense systems, the Turkish Air Force failed to destroy several dozens of missiles fired from the territory of neighboring Syria.
The S-400 Triumf (NATO reporting name: SA-21 Growler) is Russia's next-generation mobile surface-to-air missile system equipped with three different types of missiles capable of destroying aerial targets at a short-to-extremely-long range.