Iran renews nuclear weapons development

By Con Coughlin and Tim Butcher

Nuclear experts responsible for monitoring Iran's nuclear programme have discovered that enough enriched uranium, which if processed to weapons grade level could be used to make up to six atom bombs, has disappeared from the main production facility at Isfahan.

American spy satellites have identified a number of suspicious sites, which the Iranians have not declared to nuclear inspectors, that intelligence officials believe are being used for covert research.

The new discoveries emerged as it was revealed that Israel had asked America for military supplies, including "bunker buster" bombs and re-fuelling planes, suitable for an attack on Iranian nuclear installations.

The Israeli paper Haaretz reported yesterday that Israel has also asked for permission to use an air corridor through Iraqi airspace, currently controlled by America, to Iran.

So far the requests have been turned down by Washington, which is currently not as keen as Israel to consider a military strike against Iran.

But concern that Iran has resumed work on building atom bombs has deepened following the revelation that large quantities of uranium has gone missing from Iran's conversion facility at Isfahan.

The Isfahan complex, which enriches raw uranium "yellow cake" into material that can be used for either nuclear power or atomic weapons, is supposed to be subject to close supervision by the Vienna-based International Atomic Energy Agency (IAEA). But the Iranians only allow IAEA inspectors access to the final stage of the production process, where the uranium in gas form - UF6 - is stored.

By conducting a careful study of the amount of material stored at Isfahan, and the amount of "yellow cake" known to have been processed at the plant, nuclear experts believe between 50-60 tons of uranium - which if enriched to weapons grade level would be sufficient to produce five or six atom bombs - has gone missing from the plant.

IAEA officials believe the Iranians have deliberately removed the uranium at a stage in the production process that is not under their supervision. "The inspectors only have limited access at Isfahan, and it looks as though Iranian officials have removed significant quantities of UF6 at a stage in the process that is not being monitored," said a nuclear official. "If Iran's nuclear intentions are peaceful, then why are they doing this?" Nuclear inspectors have also been concerned to discover that Gholamreza Aghazadeh, the head of Iran's Atomic Energy Organisation, recently ordered scientists to increase the amount of UF6 being diverted from Isfahan to another storage facility.

IAEA officials have no idea where the missing uranium is being stored, but suspect it could be held at one of several suspicious installations that have been spotted by American spy satellites.

The Iranians will be asked to give a full account of the missing enriched uranium when the IAEA's board of governors meets in Vienna later this month to discuss the continuing crisis over Iran's nuclear enrichment programme.

The mounting concern over Iran's nuclear intentions has intensified Israeli efforts to prepare for a possible pre-emptive strike on Iran, which has led Jerusalem to presenting Washington with a "wish list" of military equipment.

In the past America has been prepared to provide Israel with "bunker buster" bombs, known by their serial number GBU-28. They weigh over two tons each and are designed to penetrate deep underground, even through reinforced concrete, before detonating.

Israel used them in unsuccessful attempts to take out the leadership of Hizbollah, the militant Shia group, during the war of 2006.