By Zahra Hosseinian, Hossein Jaseb in Tehran and Mark Heinrich in Vienna
UN nuclear watchdog seeking answers to intelligence allegations Tehran researched nuclear weapons.
The UN nuclear watchdog's top investigator will visit Tehran next week to seek Iranian answers to intelligence allegations that the country researched how to make nuclear bombs.
Following Olli Heinonen's visit to Iran earlier this week, the UN nuclear watchdog said on Wednesday Tehran had agreed on steps to clarify the intelligence information by the end of May.
Iran had earlier dismissed the intelligence as baseless and declined to address it in detail.
"Heinonen on Monday will travel to Iran for the continuation of talks which the two sides held earlier this week," the students news agency ISNA quoted an unnamed official as saying.
In Vienna, a diplomat close to the International Atomic Energy Agency (IAEA) said Heinonen would depart on Sunday for Tehran.
The West accuses Tehran of covertly trying to build nuclear weapons. Iran denies that, saying its nuclear ambitions are peaceful and only for electricity generation.
US President George W. Bush and British Prime Minister Gordon Brown last week pledged a united effort to prevent Iran from developing a nuclear bomb, possibly by expanding sanctions against the Islamic republic.
Tehran has been hit by three rounds of UN sanctions since 2006 for defying the UN demand to halt sensitive nuclear work.
Iran said this week's talks with Heinonen, the IAEA's deputy head in charge of non-proliferation safeguards, were positive.
During a power-point presentation in February, Heinonen made diplomatic waves by indicating links in Iran between projects to process uranium, test explosives and modify a missile cone in a way suitable for a nuclear warhead.
The intelligence came variously from a laptop computer given to Washington by an Iranian defector in 2004, from some other Western countries and the agency's own inquiries.
World powers are considering enhancing a package of trade and other incentives for Iran if it stops enriching uranium, which can be used as nuclear fuel or provide material for bombs.
Iran has ruled out shelving its nuclear drive and says it is working on its own proposals to help defuse the standoff. (Reuters)