"While we do not welcome sanctions, we do not fear them either," he added.

The United States and five other major powers are negotiating a fourth set of U.N. Security Council sanctions against Iran over its refusal to halt uranium enrichment. They expect the resolution to go through within the next few weeks.

The West accuses Tehran of aiming to develop atomic weapons, but Iran says its nuclear work is for peaceful power generation.

During his 90-minute news conference, Ahmadinejad warned that if new sanctions are passed it "will mean relations between Iran and the U.S. will never be improved again."

Diplomatic ties between the two countries were severed in 1980 when Iranian militants were holding more than 50 American diplomats hostage at the U.S. embassy in Tehran.