Iran has handed over to the UN nuclear watchdog a document containing design information that could help make nuclear weapon parts, diplomats said on yesterday.
The International Atomic Energy Agency (IAEA) has been demanding that Iran hand over the document, which envoys said is a long way from being a blueprint for a nuclear weapon, for the past two years.
The document contains information about the machining and casting of uranium metal into spheres for nuclear warheads.
Iran is likely to portray the gesture as an important sign that it is cooperating fully with the IAEA in resolving questions about suspicious and secretive nuclear activities that date back two decades.
Iran argues that because of this cooperation on its past activities, it should not be punished with new sanctions for its ongoing programs, even though it is violating UN Security Council resolutions by continuing to produce enriched uranium.
IAEA officials had been permitted to see the document, but until now, Tehran has refused to let them have a copy.
So the fact that Iran had finally decided to hand it over was not, in itself, significant, one diplomat said, on condition of anonymity.
"It's like getting a ticket for speeding and then refusing to pay for the next two years. What's much more important is how and why they got hold of this document in the first place," the diplomat said.
Iran has always insisted that its atomic drive is purely to generate electricity for a growing population.
The Iranians did not disclose why they had possession of the document and what they intended to do with the information, said European officials, who spoke on condition of anonymity under normal diplomatic rules.
Iran was given the engineering drawings that could have helped it cast uranium into the precise shapes needed to build the core of a nuclear weapon as part of a larger black market offer in 1987, previous agency reports said.
The information, which was offered by Abdul Qadeer Khan, the father of Pakistan's nuclear weapons program and the head of what was the world's largest nuclear black market, came into Iran's hands as the country was covertly buying nuclear equipment for its program to enrich uranium.
Iran has told agency officials that it never asked for the data.
Some envoys see Iran's move, just days before the IAEA is scheduled to release its eagerly awaited report on Iran's disputed nuclear activities, as a bid to stave off more UN sanctions.
IAEA chief Mohamed ElBaradei is currently putting the finishing touches to his report, which sources said could be released either late yesterday or today.