"Why should we refuse? You did not take any steps on the supply of missile systems to Turkey. And we have the right to use different systems. NATO clearly said that it would not create problems. Greece has possessed S-300 systems for many years, but you have no objections to it," Erdogan said at a press briefing on Monday, referring to the US' attempts to halt its purchase of S-400 systems from Russia.
In December 2017, Russia and Turkey signed a loan agreement to supply S-400s to Ankara, with 55 per cent of the $2.5 billion contract being covered by Russian loans.
Washington has repeatedly expressed its concern over the deal. In January, a US delegation in Ankara even made an official offer to Turkey to purchase Patriot systems instead of Russian S-400s.
The Turkish president in his turn reaffirmed his country's commitment to purchasing Russian-made S-400, saying that the possible Patriot deal will not affect the Ankara-Moscow agreement.