International Atomic Energy Agency officials warned Friday that Iran has made headway with advanced uranium enrichment machines that could speed production of reactor fuel and weapons-grade material that could be used for atomic bombs, agencies report.
For years, Tehran has been seeking to replace its aging, breakdown-prone 1970s centrifuges it currently uses to refine uranium, but upgrades have been hampered by sanctions restricting access to vital components, analysts say.
However, in a sign the Islamic Republic is now making progress, a confidential IAEA report leaked to the press last week says Iran has begun installing two newer versions for larger-scale testing at a research and development site near the central city of Natanz.
According to the report Iran informed IAEA officials in June that it had also started to operate 54 of these more advanced machines on an experimental basis.
If Iran does eventually succeed in introducing them in industrial quantities for enrichment, it would significantly shorten the time needed to stockpile material that has dual civilian-military uses.
"The installation of ... IR-2s and IR-4s represents progress, for sure," nuclear proliferation expert Mark Fitzpatrick told Reuters, referring to the names of the new models.
But analysts said it was not evident that Tehran has the technical prowess and components to make them in bigger numbers, especially in light of sanctions that disallow importing critical centrifuge components - or the know-how to make them.
"Iran still faces problems developing these new centrifuges, including getting sufficient materials to build them in large numbers," Peter Crail of the US-based Arms Control Association told the AFP.
In a sign deployment of the more advanced models for production remains some time off, Iran is planning to use the old IR-1 model when it shifts higher-grade enrichment from its main Natanz plant to a bunker near the central city of Qom.
"Although Iran could possibly use these (IR-1) machines to produce weapons-grade uranium ... it would likely prefer to develop its advanced centrifuges first," Crail said.
Iran denies Western claims it is covertly seeking nuclear weapons capability, saying it is refining uranium for electricity generation and medical applications.
But the IAEA has repeatedly complained Iran is impeding its inspections under the Nuclear Non-Proliferation Treaty - to which Iran is a signatory - and has sought technical knowledge specific to the manufacture of implosion devices - an atomic bomb more advanced than those used on Hiroshima and Nagasaki.
As a result, the report submitted by IAEA officials to the UN Security Council last week said the nuclear watchdog was "increasingly concerned" Iran's nuclear program had military aims.
This and other findings in the report may provide more ammunition for Western condemnations of Iran's nuclear activities when the 35-nation governing board of the IAEA meets on Sept. 12-16.
Iran's decision in early 2010 to raise the level of some enrichment from the 3.5 percent purity needed for normal power plant fuel to 20 percent worried Western states that saw this as a significant step towards the 90 percent needed for bombs.
The latest IAEA report said Iran had now produced a total of 70 kg of the higher-grade material, still well below the amount needed for a bomb, if refined further to 90 percent.
But the Institute for Science and International Security, a Washington-based think-tank, told Reuters the monthly output rate of 20 percent enriched uranium had "increased significantly."