Iran in major nuclear expansion, U.N. oversight harder

By Mark Heinrich

VIENNA (Reuters) - Iran has significantly expanded uranium enrichment with almost 5,000 centrifuges now operating and this has made it harder for U.N. inspectors to keep track of the disputed nuclear activity, an IAEA report said on Friday.

Obtained by Reuters, the restricted International Atomic Energy Agency report said Iran had increased its rate of production of low-enriched uranium (LEU), boosting its stockpile by 500 kg to 1,339 kg in the past six months.

Iran's improved efficiency in turning out potential nuclear fuel is sure to fan Western fears of the Islamic Republic nearing the ability to make atomic bombs, if it chose to do so.

Oil giant Iran says it wants a uranium enrichment industry solely to provide an alternative source of electricity.

But it has stonewalled an IAEA investigation into suspected past research into bomb-making, calling U.S. intelligence about it forged, and continues to limit the scope of IAEA inspections.

David Albright of the Institute for Science and International Security, a think tank that tracks proliferation issues, said Iran now had accumulated enough LEU to convert into high-enriched uranium (HEU) sufficient for one atom bomb.

This would require reconfiguring Iran's centrifuge network and miniaturising HEU to fit into a warhead -- technical hurdles that could take 1-2 years or more -- and would not escape the notice of U.N. inspectors unless done at an undeclared location.

There are no indications of any such secret site.