The International Atomic Energy Agency has raised concern about possible further secret nuclear sites in Iran, beyond the enrichment site at Qom that was revealed nearly two months ago, Reuters reported, quoting an IAEA report the news agency obtained Monday.
According to the document, Iran told the IAEA it had begun building the site at Qom, called Fordo, in 2007 - but the IAEA, the United Nations' global nuclear proliferation watchdog, had evidence the project had begun in 2002, paused in 2004 and resumed in 2006.
The report said Iran had provided full access to IAEA inspectors on their first visit to the Qom site three weeks ago, but had yet to provide full, credible answers to verify that the plant was only for civilian purposes.
"The agency has indicated [to Iran] that its 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 not declared to the agency. Moreover, Iran's delay in submitting such information to the agency does not contribute to the building of confidence," The report states.
The IAEA also said Teheran had yet to give answers about the site's chronology and purpose.
The report also said that Iranian technicians have moved highly sophisticated technical equipment into the previously secret uranium enrichment site in preparation for starting it up in 2011.
The document offered no estimate of the new plant's capabilities, but a senior international official familiar with the watchdog agency's work in Iran said it appeared designed to produce about a ton of enriched uranium a year.
That would be enough for a nuclear warhead, but too little to fuel the nearly finished plant at the southern port of Bushehr and other civilian reactors Iran is planning to bring on line in the coming years.
The IAEA also noted that Iran's enrichment at the Natanz site - revealed by dissidents in 2002 and under agency monitoring - was stagnating, with output remaining at mid-2009 levels.
The report did not offer a reason. But the official suggested that nuclear experts previously working at Natanz could now be preoccupied with putting the finishing touches on the newly discovered Fordo site.
As early as three years ago, Iranian officials had announced that immediate plans for the Natanz site were to install about 8,000 enriching centrifuges, and Monday's report suggested that Teheran had reached that goal.
The seven-page report - the latest IAEA summary of what it knows about Iran - said that as of November 2, about 8,600 centrifuges had been set up, but only about 4,000 were enriching - or 600 fewer than in September.
Still, the official said output had been steady since June, with about 100 kg. of enriched uranium being produced a month.
The report said that Natanz had churned out close to 1,800 kg. of low-enriched, or nuclear fuel-grade uranium by November 2 - close to the amount considered by experts that would be needed for two nuclear weapons.
But the report's main focus was Fordo, a highly fortified underground space. Iran informed the IAEA only in September that it was building the facility, leading the US, British and French leaders to denounce Teheran for keeping its existence secret.
IAEA inspectors visited the plant last month and the report noted "an advanced stage of construction," with support equipment for centrifuges already in place.
Iran says it fulfilled its legal obligations when it revealed the plant's construction, although IAEA chief Mohamed ElBaradei has said Teheran was "outside the law" and should have informed his agency when the decision to build was made.
Nations suspicious of Teheran's nuclear program believe the Islamic Republic decided to inform the IAEA only after it became convinced that the plant's existence had been noted by foreign intelligence services - and was about to be revealed by Western leaders.
A senior Western official recently told The Associated Press that Fordo appeared too small to house a civilian nuclear program but large enough to serve for military activities.
Monday's report - prepared for a meeting next week of the IAEA's 35-nation board - did not address the issue of size or function, beyond saying that the Fordo facility would house about 3,000 centrifuges, which the senior international official said could turn out about just over a ton of enriched uranium annually.
Fordo's existence has heightened concerns of other possible undeclared facilities that are not under IAEA purview and therefore can be used for military purposes
Also on Monday, Russian news agencies reported the reactor at the plant that Russia is building near Bushehr will not be switched on this year as planned.
The agencies quote Energy Minister Sergei Shmatko as saying that while Moscow expects to make "serious progress" by the end of the year, "there will be no startup."
Officials in Russia and Iran previously announced plans to switch on the reactor this year.
Russia also says Iran must not acquire nuclear weapons, but it has close ties with Teheran and has pledged to complete the more than decade-old project.
Meanwhile, Iranian President Mahmoud Ahmadinejad said that an impasse in nuclear talks between world powers and Iran would only hurt the West by making Teheran push harder to advance its technology.
Ahmadinejad's comments can be seen as a veiled threat that Iran would go ahead with enriching uranium to a higher level should negotiations with the international community fail.
"Cooperation with Iran is in the West's interest," while pressures on the Persian nation would only make the country "more powerful and advanced," he said, according to a statement posted late Sunday on the presidential Web site.
Ahmadinejad also reiterated that Iran's nuclear rights are not negotiable and that the country's nuclear activities would only continue within the framework of the UN nuclear watchdog. The Web statement did not elaborate on how Western pressure would embolden Iran.
But it's a likely reference to enriching uranium to a higher level of 20 percent, needed to power a research reactor in Teheran that is part of the negotiations with the IAEA in Vienna.
Iran is currently enriching uranium to less than 5%, which is sufficient to produce fuel for its future nuclear power plant, but has also raised fears in the West of a covert further enrichment by Teheran in a secret nuclear arms pursuit.
Meanwhile, IAEA inspectors have demanded to visit a suspected nuclear Syrian site at Dir Azur on Tuesday, Channel 10 cited foreign media reports on Monday night.
According to the report, UN nuclear watchdog inspectors who visited the site after it was destroyed by the IAF in September 2007, found highly processed plutonium, indicating that Syria's nuclear program was further along than was previously assessed.
However, Channel 10 stated is was not clear whether authorities in Damascus would allow the inspectors into the site.