VIENNA (AFP) -Iran has handed over to the UN nuclear watchdog a document containing design information that could help to make nuclear weapon parts, diplomats said on Wednesday.

The International Atomic Energy Agency (IAEA) has been demanding that Iran hand over the document, which diplomats said is a long way from being an actual 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.

IAEA officials had previously 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, while the United States accuses it of seeking to develop a nuclear bomb.

Tehran should now focus on answering all of the IAEA’s outstanding questions without delay, the diplomat said.

Some diplomats see Tehran’s move, just days before the IAEA is scheduled to release its eagerly-awaited report on Iran’s disputed nuclear activities, as a last-minute attempt 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 late Wednesday or on Thursday.

ElBaradei’s report, along with a second by the EU’s foreign policy chief Javier Solana set to be released later this month, could persuade the UN Security Council in New York to impose a third round of sanctions against Iran if the reports’ findings are negative.

Other diplomats see the latest move by Iran as a sign of progress that the Islamic republic is finally co-operating with the IAEA and coming clean about the details of its past nuclear activities.