The S-400 missile system is necessary for Turkey's defense and sovereignty, the Nationalist Movement Party (MHP) Chair Devlet Bahçeli said Tuesday as he criticized the United States for its shift in attitude following Ankara's purchase of the advanced Russian defense equipment.

Bahçeli remarked at a parliamentary group meeting in the capital Ankara that the Biden administration "has obviously no good feelings for Turkey" because of its position on several issues, including the purchase of S-400 from Russia.

"Let me tell you something the U.S. administration doesn't know, Turkey respects human rights much more than they do," he added.

"The S-400 issue is within the boundaries of our sovereignty, and anyone's indiscretion to set a course for Turkey on this issue will not be left unanswered," he noted.

Turkey’s initial purchase of S-400s from Russia strained ties with the United States. The move prompted Washington to remove Turkey from the new generation F-35 Lightning II jet program. The U.S. had also threatened to impose new sanctions if Turkey buys more major arms systems from Moscow.

The U.S. argued that the system could be used by Russia to covertly obtain classified details on the Lockheed Martin F-35 jets and that it is incompatible with NATO systems. Turkey, however, insists that the S-400 would not be integrated into NATO systems and would not pose a threat to the alliance.

Previous talks on Turkey’s purchase of U.S.-made Patriots collapsed over a host of issues, from the S-400s to Ankara’s dissatisfaction with Washington’s terms. Turkey has said it will only agree to an offer if it includes a technology transfer and joint production terms.

The U.S. sanctioned Turkey in 2020 for its purchase under a 2017 law aimed at pushing back Russian influence. The move was the first time that the law, known as Countering America's Adversaries Through Sanctions Act (CAATSA), was used to penalize a U.S. ally.