The US Central Intelligence Agency (CIA) has warned that international inspections may not prevent Iran from pursuing nuclear weapons, because Tehran could be using legitimate fuel production to cover up its weapons program.
The assessment, contained in a report to Congress made public over the weekend, coincided with Iran's formal assurances to the International Atomic Energy Agency (IAEA) that it will accept surprise UN inspections of its nuclear facilities and suspend its uranium enrichment program.
The two promises had been requested by the IAEA ahead of its Nov. 20 meeting to assess Iran's compliance with the nuclear Non-Proliferation Treaty.
But the CIA said that a secret nuclear facility at Natanz whose existence was disclosed by members of the Iranian opposition in August last year could be cause for concern.
About 160 new centrifuges for enriching uranium have subsequently been discovered at that complex, located between the cities of Isfahan and Kashan in central Iran, according to US and UN officials.
"Even with intrusive IAEA safeguards inspections at Natanz, there is a serious risk that Iran could use its enrichment technology in covert activities," warned the leading US intelligence agency.
It added that the uranium centrifuges discovered at Natanz were "of specific proliferation concern" because they are capable of enriching uranium for use in nuclear weapons.
"Although Iran claims that its nascent enrichment plant is to produce fuel for the Russian-assisted construction projects at Bushehr and other possible future power reactors, we remain concerned that Iran is developing enrichment technology to produce fissile material for nuclear weapons under the cover of legitimate fuel cycle activities," the CIA said.
The report insisted that Iran appears to be trying to produce both known materials for making nuclear warheads: highly enriched uranium and low burn-up plutonium.
According to the CIA, commercial satellite imagery showed that Iran was trying to bury the Natanz enrichment facility in the ground, presumably to hide it or harden it against military attack.
"We also suspect that Tehran is interested in acquiring fissile material and technology from foreign suppliers to support its overall nuclear weapons program," the report said.
Iran is also trying to expand its arsenal of delivery systems that can be used to carry weapons of mass destruction, according to US intelligence experts.
In the first half of this year, it continued to receive equipment, technology and expertise from companies in the former Soviet Union, North Korea and China that could eventually help Tehran move toward its goal of becoming self-sufficient in the production of ballistic missiles, the agency said.
Iran's ballistic missile arsenal includes some medium-range Shahab-3 capable of hitting targets 1,300km away and a few hundred short-range ballistic missiles, like Shahab-1, Shahab-2 and Tondar-69, according to defense experts.
The CIA also insisted that despite its participation in the Chemical Weapons Convention, Tehran has continued to seek production technology, training and expertise from Chinese firms that could further its efforts to achieve an indigenous capability to produce nerve agents.
"Iran likely has already stockpiled blister, blood, choking, and probably nerve agents and the bombs and artillery shells to deliver them which it previously had manufactured," the report said.