"This is over," Erdogan said, noting the signatures had already been made on the deal and that the first delivery will be made in July. "We are an independent Turkey, we are not slaves."
US Army General Curtis Scaparrotti, who heads US European Command, recommended to the US Congress on Tuesday that if Turkey presses ahead with buying the S-400 systems from Russia, delivery to Turkey of Lockheed Martin's F-35 Joint Strike Fighter should be cancelled.
"If they accept the S-400 and establish it within Turkey, there is an issue […] that has to do with the F-35," the commander told the Senate Armed Service Committee, Sputnik reported. "It presents a problem to all of our aircraft, but specifically the F-35. My best military advice would be that we don't then follow through with the F-35, flying it or working with an ally that's working with Russian systems, particularly air-defense systems, with what I would say is probably one of most advanced technological capabilities."
The Turkish president also mused that his government might later consider buying Russia's top-of-the-line S-500 Prometey (Prometheus) air defence systems at a later date. The S-500 isn't even fully operational with the Russian Armed Forces yet, but is believed it will be equal in capability to the US Terminal High Altitude Air Defense (THAAD) system once it enters service in 2020.
He went on to say that the US shouldn't try to discipline Turkey through trade measures, noting that Turkey has its own measures prepared.
Washington has repeatedly threatened to slap sanctions on Ankara under the Countering America's Adversaries Through Sanctions Act (CAATSA) if Turkey buys Russia's S-400s, Sputnik reported.
Erdogan's Wednesday comments also touched on the US withdrawal from Syria, where Ankara and Washington have found themselves on opposite sides of Turkey's ongoing conflict with Kurdish militias in the region.
"If US is to take weapons out of Syria, they can, but if they won't, give them to Turkey, not terrorists," Erdogan said in a TV interview with broadcaster Kanal 24. Ankara considers Kurdish militias like those that comprise the US-backed Syrian Democratic Forces to be terrorist organizations. As the US timetable for withdrawal from Syria continues, Washington has weighed the question of whether or not to take lent US weapons with them or to leave them in Kurdish hands to continue the fight against Daesh* and other forces in the country.
Erdogan said that, while he believes US President Donald Trump has "taken a firm stand" on withdrawing US troops from Syria, he faces pressure from the US state apparatus. "There's a established order in the US," Erdogan said. "We can also call this 'deep state.' They block these steps."
*Daesh, also known as Islamic State (IS), ISIS or ISIL is a terror group banned in US, Russia and many other countries.