* Iran doubles uranium enrichment capacity in bunker
* But it may struggle with developing more modern models
* Faster centrifuges could allow quicker atom bomb breakout
* Iran denies nuclear weapon aims, says work peaceful
By Fredrik Dahl
VIENNA, Aug 31 Iran may have doubled its uranium
enrichment capacity in an underground facility but it seems to
be struggling to develop more efficient nuclear equipment that
would shorten the time it would need for any atom bomb bid,
Iran's progress - or lack of it - in deploying a new
generation of enrichment centrifuges is closely watched by the
West as it could allow it to produce potential weapons-grade
material much faster. Tehran denies this is its aim.
"Iran appears to be continuing to encounter problems in its
testing of production-scale cascades of advanced centrifuges," a
U.S. think-tank, the Institute for Science and International
Security (ISIS), said.
Cliff Kupchan, a Middle East analyst at consultancy Eurasia
Group, said: "I note that the real game-changer, the advanced
centrifuge programme, still seems to be failing."
Tehran says it is refining uranium to fuel a planned network
of nuclear power plants so that it can export more of its oil
and gas. The United States and its allies accuse it of a covert
bid to develop nuclear bombs.
Iran has sharply increased the number of centrifuges it has
in the fortified Fordow bunker, a U.N. report said on Thursday,
showing Tehran has continued to expand its nuclear programme
despite Western pressure and the threat of an Israeli attack.
Iranian lawmaker Kazem Jalali said the report's publication
during a meeting in Tehran of developing countries was
politically motivated, the ISNA news agency reported.
The IAEA report also said buildings had been demolished and
earth removed at a military site it wants to inspect. The West
believes Tehran is removing evidence of illicit nuclear-linked
tests, but Foreign Minister Ali Akbar Salehi said "such things
can not be cleaned up or removed," ISNA quoted him as saying.
The quarterly IAEA report may strengthen a belief in Israel
- which sees Iran's nuclear programme as a threat to its
existence - that the West's tougher economic sanctions against
Tehran this year are failing to make the major oil producer curb
But the International Atomic Energy Agency (IAEA) report
said the newly-installed machines, which are not yet operating,
were all so-called IR-1 centrifuges - a 1970s-vintage model
which has been prone to breakdowns in the past.
Iran has for years been trying to introduce centrifuges with
several times the capacity of the IR-1 version it now uses for
the most sensitive part of its atomic activities.
If it eventually succeeded in deploying the newer models for
large-scale enrichment, it could significantly reduce the time
needed to stockpile refined uranium, which can be used to
generate electricity or, if processed much further, nuclear
LIMITED IRAN KNOWLEDGE
But it is unclear whether Tehran, subject to increasingly
strict international sanctions, has the means and components to
make the more sophisticated machines in bigger numbers.
The U.N. Security Council has long called on Iran to suspend
uranium enrichment and Tehran's failure to comply has earned it
four rounds of sanctions, as well much tougher U.S. and European
Union measures that take direct aim at its biggest export, oil.
Marking a potential step forward, Iran last year started
installing more IR-4 and IR-2m models for testing at a research
and development site at its enrichment facility near the central
town of Natanz.
But the IAEA report suggested it was not making major
progress, saying it was "intermittently" feeding uranium gas
into these machines. In addition, the U.N. agency said Iran had
yet to install three other models which it had said it would.
The IAEA report "confirms that those machines are still not
ready for full-scale use," the Arms Control Association, a
U.S.-based research and advocacy group, said.
The IAEA, which regularly inspects Iran's declared nuclear
sites, has little access to facilities where centrifuges are
assembled and the agency's knowledge of possible centrifuge
progress is mainly limited to what it can observe in Natanz.
Tehran often trumpets technical advances in its nuclear
programme, including the development of new centrifuges -
machines that spin at supersonic speed to increase the
concentration of the fissile isotope in uranium.
Early this year, President Mahmoud Ahmadinejad said Iran had
a "fourth generation" centrifuge that could refine uranium three
times faster than previously.
"Given the time taken for R&D (research and development) on
Iran's second-generation machines, it is probably quite some
time before Iran is ready to use these additional models," the
Arms Control Association said in reference also to plans for
even more sophisticated machines known as IR-5, IR-6 and IR6s.