Stephen Castle and Anne Penketh
Tension over Iran's nuclear programme heightened last night after the United Nations nuclear agency confirmed that Tehran has crossed a new threshold by producing fuel in its underground uranium enrichment plant.
The confirmation, contained in a letter signed by Olli Heinonen, the International Atomic Energy Agency's deputy director general, follows a visit to the Natanz enrichment plant in Iran by nuclear inspectors. But the country is still believed to be a year or so away from the point of no return, which Israel regards as a red line in the Iranian quest for a nuclear capability.
The letter, dated 18 April, says that Iran was now running more than 1,300 centrifuges and had begun feeding small amounts of uranium gas into them. Centrifuges produce nuclear fuel for energy or for a bomb, depending on the level of enrichment. The IAEA also said that Iran had managed to link the centrifuges into eight cascades, suggesting that scientists had mastered a further stage of the complex and notoriously unreliable process.
The IAEA confirmation follows an announcement by Mahmoud Ahmadinejad, the Iranian President, who boasted last week that Iran had now joined the nuclear club of nations, while the country's chief negotiator said that enrichment was taking place on an "industrial scale".
However, the IAEA does not appear to confirm that all 1,300 of the centrifuges are actually operating. As of last year, just over 300 were spinning to enrich uranium but experts said that the Iranians were experiencing difficulties in sustaining the operation. Iran, which has consistently defied international demands to rein in its nuclear programme, plans to have 3,000 centrifuges running in a month.
The IAEA also complained of Tehran's decision to prevent UN inspectors visiting the country's heavy water reactor, which can also be used in production of a bomb. Both the uranium enrichment and the restrictions on the inspectors violate UN Security Council resolutions demanding that Iran stop enriching uranium because of fears that Tehran's supposedly civilian nuclear fuel programme is a cover for building an atomic weapons. Coming hard on the heels of the recent crisis over the British sailors captured by Iranian forces, the claims could to bring Tehran closer to confrontation with the West. The Security Council is due to discuss Iran's compliance next month.
The latest report coincided with a visit to Israel and Egypt by Robert Gates, the US Defence Secretary. Israel's ambassador to the United States, Sallai Meridor, said it appeared that Tehran was going "full speed" with its effort to have mastered the technology of enriching uranium needed to produce a bomb and that world powers must act.
He said in an interview with Reuters: "We are extremely concerned by Iran's continued effort to expand their enrichment activities. It seems that they are developing a large-scale centrifuge plan."
The International Institute for Strategic Studies reported in January that it is likely to take about a year for Iran to be able to manage to run 3,000 centrifuges in linked cascades.
"If and when Iran does have 3,000 centrifuges operating smoothly, the IISS estimates it would take an additional nine to 11 months to produce 25kg of highly enriched uranium, enough for one implosion-type weapon. That day is still two to three years away at the earliest," the IISS said in its annual report, The Military Balance.
Iran claims it wants to enrich only to lower levels suitable to generate nuclear power, and insists on its right to peaceful nuclear activities. But IAEA suspicions about its ultimate intentions have led to UN Security Council sanctions for its refusal to freeze its enrichment programme