UN: Iran can build nuclear warhead

Iran has enough low-grade enriched uranium to build a nuclear weapon, says the UN's nuclear watchdog.

Iran has enough low-grade enriched uranium to start building a nuclear weapon, the UN's nuclear watchdog said, following the discovery that the Islamic republic has more of the material than it previously disclosed. The country now has 1,010kg of enriched uranium, the International Atomic Energy Agency (IAEA) revealed in a report, meaning it has crossed the threshold of 1,000kg needed to build a single warhead.

The report will stir fears that Iran has taken another significant step towards acquiring a bomb and may complicate the possibility of rapprochement with the US after weeks of both countries making cautiously conciliatory remarks. An additional 209kg of low-grade enriched uranium has been processed at the Natanz plant, a third more than Iran admitted to IAEA inspectors last year, but Iranian officials told the UN they simply miscalculated the figures, The New York Times reported. The agency was aware of the error last November but did not publicise it.

Christopher Pang, head of the Middle East and Africa programme at Rusi, a defence and security think tank in London, said the development will improve Iran's bargaining position. "The breakout capacity has provided Iran with a new strategic option. It strengthens Iran's ability to continue negotiations. It is a novel development. "But it doesn't actually tell us a great deal if Iran has made a decision to, or is capable of, making a nuclear bomb."

There are still many practical obstacles in the way, he said. The uranium would have to be further enriched to weapons grade - a lengthy process - while designing a missile that could deliver a warhead and fitting the weapon on the missile required highly sophisticated technology. Earlier this month, Iran launched a satellite into space, causing alarm in the West and among its allies in the region about Tehran's acquisition of rocket missile technology. Iran said it was for scientific purposes, but the Pentagon said it could be used to propel long-range ballistic missiles.

The one tonne of low-grade enriched uranium must undergo further refining before it can be purified into 20 to 25kg of the high grade material needed for a bomb and the atomic agency reported it has not seen evidence of this. Iran has slowed down its expansion of producing centrifuge machines that are needed to produce nuclear fuel, the agency said in the report to its board. The Natanz plant has a confirmed 4,000 centrifuges, which spin to enrich uranium into nuclear fuel, up from 3,800 last November. The increase was small, but another 1,500 may be under construction.

Mohamed ElBaradei, the head of IAEA, said earlier this month that Iran appeared to have made "a political decision" to produce less enriched uranium than it was capable of. Iran has been adamant that its nuclear ambitions are for peaceful use because it wants to generate electricity for a growing population and sell its oil reserves abroad. But the lack of transparency and failure to allow inspectors full access have created fears that it has ulterior motives.

Iran has prevented UN inspections of its facilities manufacturing centrifuge parts and a heavy water site at Arak, so there are concerns the country may be building facilities in addition to the one at Natanz. David Albright, a veteran UN weapons inspector, who now heads the independent Institute for Science and International Security in Washington, told the Guardian newspaper: "They have reached a nuclear weapons break out capability. If they break out they will do it at a clandestine facility, not at Natanz, so you can't use Natanz as a measure of how fast they could do it. The Iranians have stopped telling the IAEA about the production of centrifuges ? so the agency doesn't know how many they are making."

UN officials told the New York Times there was no possibility that Iran could smuggle enriched uranium out of the plant for further processing at a secret location. The stockpile is under IAEA surveillance. With additional reporting by Reuters [e-mail]