Iran has again rejected U.S. and British accusations that it is trying to develop nuclear weapons, a day before the visit from a top U.N. nuclear agency official.

A spokesman for the Iranian foreign ministry said Sunday the allegations Iran is working toward a nuclear weapon are untrue.

Deputy Director General of IAEA, Olli Heinonen

The International Atomic Energy Agency says its deputy chief, Olli Heinonen, is due in Tehran Monday for talks with Iranian officials.

Heinonen is expected to address persistent allegations that Iran is running a secret nuclear weapons program.

The IAEA has said it is still unable to confirm the nature of Iran's nuclear program.

The United Nations Security Council has imposed three sets of sanctions on Iran for its failure to suspend uranium-enrichment activities.

Highly enriched uranium can be used in nuclear weapons, but Tehran says its program is purely peaceful.

The United States and other Western countries have accused Iran of trying to develop nuclear weapons.

On Saturday, Iran's official news agency, IRNA, reported that Minister of Industries and Mines Ali-Akbar Mehrabian said U.N. sanctions have had no effect on Iran's industrial progress.

He was quoted as saying the nation's industries are thriving, despite the sanctions.

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