Iran's Supreme Leader Ayatollah Ali Khamenei says Tehran may someday resume diplomatic relations with the United States, but that now is not the right time because there is no benefit for Iran.

Iranian state media quoted Khamenei as making his remarks Thursday to students in the central city of Yazd.

Khamenei said having no relations with the United States is one of Iran's main policies, but that Tehran has never said those relations should be cut forever. He said resuming ties now would be "harmful" to Iran.

Iran's supreme leader also said his country will not halt work on its nuclear program.

Khamenei has the final word on all state matters in Iran.

U.S.-Iranian relations were severed after Iran's 1979 Islamic Revolution and the U.S. embassy takeover by militants in Tehran.

The two countries are now at odds over Iran's controversial atomic work and on who is to blame for the violence in Iraq.

The United States and other Western nations accuse Iran of seeking to build nuclear weapons under the cover of a civilian energy program. Tehran denies the charge.

Some information for this report was provided by AFP, AP and Reuters.