The UN atomic watchdog demanded on Monday more information from Iran about the purpose of a previously secret nuclear site and indicated the Islamic republic could be hiding other facilities.

The International Atomic Energy Agency also said it had been told by Iran in a letter that a new site near the holy city of Qom should be operational in 2011, heightening fears Tehran is edging closer to developing a nuclear bomb.

"Iran's declaration of the new facility reduces the level of confidence in the absence of other nuclear facilities under construction and gives rise to questions about whether there were any other nuclear facilities in Iran which (have) not been declared to the agency," said the new IAEA report.

"Iran's explanation about the purpose of the facility and the chronology of its design and construction requires further clarification," it said, confirming that uranium enrichment activities continued despite UN sanctions.

Iran revealed to the IAEA in September that it had built a second uranium enrichment plant inside a mountain near Qom, triggering new outrage in the West over the nuclear drive, even though Iran denies it is trying to build a bomb.

'Running out of time'

US President Barack Obama said before Monday's IAEA report that Iran was "running out of time" to accept a deal whereby other nations would enrich its uranium.

Under the UN-backed deal, Iran would rely on Russia and France to process low-enriched uranium to fuel a Tehran reactor that makes medical isotopes.

The Islamic republic would be left without sufficient material to make a nuclear weapon, at least from stockpiles known to the international community.

Obama has been pursuing a stick-and-carrot approach on Iran, offering engagement at the same time as threatening sanctions, but US officials warned again on Monday, after the IAEA report, that patience was wearing thin.

"Now is the time for Iran to signal that it wants to be a responsible member of the international community," State Department spokesperson Ian Kelly said in a statement.

Iran has been enriching uranium for several years at a plant in the central city of Natanz, in defiance of three sets of UN sanctions. Uranium is used for fuel for civilian reactors, but in highly enriched form can also make the fissile core of an atomic bomb.

In its first official report since IAEA experts inspected the Qom site last month, the watchdog said Tehran's delay in disclosure "does not contribute to the building of confidence."

The agency said it had acquired satellite images indicating some sort of construction work had taken place there between 2002 and 2004 and had resumed in 2006.

A back-up plant?

Iran said the site was planned as a back-up plant should the Natanz plant be bombed, for example, and work on turning it into such a facility began in the second half of 2007.

Even if that were true, the IAEA stated: "Iran's failure to notify the agency of the new facility until September 2009 was inconsistent with its obligations."

During the visit to the Qom site last month, IAEA inspectors verified that the plant "was built to contain 16 cascades with a total of approximately 3000 (uranium-enriching) centrifuges," the report stated.

The Natanz plant currently has around 8000 centrifuges installed.

No centrifuges had been installed in Qom, but the plant was "at an advanced stage of construction," the IAEA said, adding that Iran gave the inspectors "access to all areas of the facility."

The IAEA said it told Tehran it still had questions about how the facility fitted into Iran's nuclear programme and had requested access to the plant project manager and those responsible for its design.

Earlier in Tehran, President Mahmoud Ahmadinejad reaffirmed that Iran's nuclear rights were "non-negotiable". He said the "enemies" of the nuclear programme had been defeated.

Tehran's envoy to the IAEA, Ali Asghar Soltanieh, said Iran would continue uranium enrichment and dismissed the constant stream of IAEA reports as "repetitive and tedious."

"Iran will continue to exercise its right to peaceful use of nuclear energy, including enrichment," Soltanieh told Fars, Iran's semi-official news agency.

AFP

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