The Islamic Republic, which denies its programme has military aims, defied the international community by announcing on Sunday that it would enrich uranium to 20% purity for a Tehran reactor making medical isotopes for cancer patients.
As tensions with the West rose and Russia indicated it could back fresh UN sanctions, members of an Islamic militia threw stones at the Italian embassy in Tehran.
The big powers have stepped up discussions on what form a possible fourth set of UN sanctions over its still-expanding nuclear programme could take.
US Defence Secretary Robert Gates said: “I think it’s going to take some period of time — I would say weeks, not months — to see if we can’t get another UN Security Council resolution,” according to the transcript of his interview.
State television quoted Iranian nuclear agency chief Ali Akbar Salehi, saying that “enrichment to 20% started in the Natanz facility under the supervision of the (International Atomic Energy Agency)”. This followed a failure to agree on a swap with major powers, under which Iran would send most of its low-enriched uranium abroad in return for 20%-pure fuel rods for the reactor. Western powers fear Iran is enriching uranium with a view to producing nuclear weapons.
Iran currently enriches uranium to 3.5% purity.
Salehi said Iran had set up a chain of 164 centrifuges to refine the uranium to 20% purity. He said the production capacity was 3kg to 5kg a month, above the Tehran reactor’s needs of 1.5kg, reported ISNA news agency.
Although a nuclear bomb requires about 90% purity, getting to 20% is a big step because low-level enrichment is the most time-consuming and difficult stage of the process.
Iran currently has nonuclear power plants able to use the low-enriched uranium it has already produced, and lacks the technology to convert the 20% pure uranium into the fuel rods needed to run the medical reactor.
“I think Iran all along intended to enrich to 20%, ostensibly to supply the research reactor but also to gain experience enriching to higher levels that would prove useful for weapons production,” said Mark Fitzpatrick, proliferation expert at the International Institute for Strategic Studies.
Russia, which in the past has urged talks rather than punishment, said Iran’s move was a clear breach of UN resolutions.
Among the big powers only China, which can block any UN sanctions, has remained unswervingly opposed to punishing Iran.