Iran appears to have worked on designing an atomic bomb and may still be conducting relevant research, the U.N. nuclear watchdog said in a hard-hitting report on Tehran's nuclear program likely to raise tensions in the Middle East.
Citing what it called "credible" information from member states and elsewhere, the agency listed a series of activities applicable to developing nuclear weapons, such as high explosives testing and development of an atomic bomb trigger.
The hotly anticipated International Atomic Energy Agency report, which was preceded by Israeli media speculation of pre-emptive air strikes on Iranian nuclear sites by Tehran's arch-foe, detailed new evidence apparently showing concerted, covert efforts to acquire the capability to produce atomic bombs.
Some of the cited research and development activities by Iran have both civilian and military applications, but "others are specific to nuclear weapons," said the report, obtained by Reuters Tuesday ahead of an IAEA board of governors meeting.
Tehran, which has denied ever seeking nuclear firepower, immediately condemned the report. "(It) is unbalanced, unprofessional and politically motivated," said Ali Asghar Soltanieh, Iran's ambassador to the IAEA.
The United States and its allies are expected to seize on the document to press for more punitive sanctions on the major oil producer over its record of hiding sensitive nuclear activity and lack of full cooperation with U.N. inspectors.
"I think the facts lay out a pretty overwhelming case that this was a pretty sophisticated nuclear weapons effort aimed at miniaturizing a warhead for a ballistic missile," said prominent U.S. proliferation expert David Albright.
"It's overwhelming in the amount of details, it is a pretty convincing case," he told Reuters from Washington.
Russia criticized the report, saying it would dim hopes for dialogue with Tehran on its nuclear strivings and suggesting it was meant to scuttle chances for a diplomatic solution.
"We have serious doubts about the justification for steps to reveal contents of the report to a broad public, primarily because it is precisely now that certain chances for the renewal of dialogue between the 'sextet' of international mediators and Tehran have begun to appear," the Russian Foreign Ministry said in a statement.
It said time was needed to study the report and determine whether it contained new evidence of a military element in Iran's nuclear program or was nothing but "the intentional — and counterproductive — whipping up of emotions."
Tehran has for years dismissed allegations of atomic bomb research, based largely on Western intelligence funneled to the IAEA, as fabricated and baseless, and more recently sought to discredit IAEA chief Yukiya Amano as a tool of Washington.
The IAEA said it had carefully assessed intelligence passed on from member states and found it consistent in terms of technical content, individuals and organizations cited and time frames. It said it had gathered its own supportive details.
"The agency has serious concerns regarding possible military dimensions to Iran's nuclear program," the IAEA said in the report, which included an unusual 13-page annex with technical descriptions of research with explosives and computer simulations applicable to nuclear detonations.
The Vienna-based agency said the data "indicates that Iran has carried out activities relevant to the development of a nuclear explosive device."
It added: "The information also indicates that prior to the end of 2003, these activities took place under a structured program, and that some activities may still be ongoing."
"STRONG INDICATORS OF WEAPONS DEVELOPMENT"
U.S. spy services estimated in 2007 that Iran had halted outright "weaponisation" research four years previously, but also that the Islamic Republic was continuing efforts to master technology usable in nuclear explosives.
The IAEA report included information from both before and after 2003. It voiced "particular concern" about information given by two member states that Iran had carried out computer modeling studies relevant to nuclear weapons in 2008-09.
"The application of such studies to anything other than a nuclear explosive is unclear to the agency," the IAEA said.
The information also indicated that Iran had built a large explosives vessel at the Parchin military complex southeast of Tehran in which to conduct hydrodynamic experiments, which are "strong indicators of possible weapon development."
Israeli officials had no immediate comment on the IAEA report, which was big news in a Jewish state that feels uniquely threatened by Iran, although Israel is widely believed to harbor the Middle East's only nuclear arsenal.
Udi Segal, diplomatic correspondent for Israel's top-rated Channel Two television news, said the report would dampen speculation that an attack on Iran was in the offing.
"First off, the prime minister has instructed the ministers to keep mum – that's a refreshing innovation. He is letting the game move over to the international community. Israel is saying, in essence, 'We told you so'," said Segal.
"They are rolling the ball to the world, so it will pass crippling sanctions, in hope this will work. De facto, it defers talk of military option for at least a few months."
A U.S. official said after the report's release that Washington might slap more sanctions on Iran, possibly on commercial banks or front companies, but is unlikely to target its lifeblood oil and gas sector or its central bank for now.
"I think you will see bilateral sanctions increasing," the official, speaking on condition of anonymity, told Reuters.
"From our side, we are really looking to close loopholes wherever they may exist," he said.
For several years the IAEA has been investigating Western intelligence reports indicating that Iran has coordinated efforts to process uranium, test high explosives and revamp a ballistic missile cone to accommodate a nuclear warhead.
Iran, the world's No. 5 oil exporter, insists that its program to enrich uranium is for a future network of nuclear power stations to provide electricity for a rapidly growing population, so that it can export more of its oil and gas.
But Tehran's history of hiding sensitive nuclear activity from the IAEA, continued restrictions on IAEA access and its refusal to suspend enrichment, which can yield fuel for atom bombs, have drawn four rounds of U.N. sanctions and separate punitive steps by the United States and European Union.
IAEA officials have often complained that Iran has refused, for at least three years, to seriously answer the agency's questions about accusations of illicit nuclear activity.