A U.S. anti-terrorism official says Iran is providing money to finance terrorism carried out by the militant group Hezbollah - calling the country quote - "the central banker of terror".

In an interview with the Associated Press Monday, Stuart Levey said Iran is a country that has terrorism as part of its budget.

Levey - the U.S. Under-Secretary of the Treasury for Terrorism - spoke as Iran faces a Thursday, August 31 U.N. deadline to stop enriching uranium or face possible sanctions.

Separately, the United States confirmed it will issue a visa to former Iranian President Mohammad Khatami, who has been invited to speak next month at a multi-faith seminar in Washington.

Khatami, considered a moderate among Iranian religious leaders, had advocated dialogue with the U.S. during his term in office, which ended last year.

The U.S. and other Western nations accuse Tehran of secretly trying to build nuclear weapons. Iran says its nuclear program is for generating electricity.

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