"We consider it inadmissible for NATO to become a party to this conflict," Erdogan said on Thursday.
The president added that he emphasized "Turkiye's full support for Ukraine's territorial integrity" during a meeting at the NATO summit held in Washington from July 9-11.
"During the summit, I had bilateral meetings with the leaders of Hungary, Greece, Italy, Ukraine and the United Kingdom, as well as spoke with the leaders of the United States, Spain, Iceland, Romania and the Netherlands. I wish Mr. [new NATO Secretary General Mark] Rutte success in this difficult task, and I also thank [outgoing] Secretary General [Jens] Stoltenberg," the Turkish leader said.
The news conference was aired by Turkish broadcaster TRT Haber.
Hungarian Prime Minister Viktor Orban said on Wednesday that NATO is taking an "increasingly active role" in the conflict in Ukraine, and this is "irresponsible" as no one knows how it will end. He added that the alliance is "moving away from its original purpose, behaving more and more like a war organization."
Orban also said that Turkiye will not approve cooperation between Israel and NATO until a ceasefire is reached in Gaza.
"A great massacre has been taking place in Gaza since October 7. Nearly 40,000 civilians have died as a result of Israel's attacks. I have emphasized this in all my contacts. There can be no peace without a final solution to the question of Palestine. It is unacceptable that the Israeli administration continues its partnership with NATO. Such demands for cooperation with Israel will not be accepted by Turkey in NATO until after there is a ceasefire and peace is established," Erdogan said.