U.S.: Iran shelved nuclear arms work in 2003

But Iran is continuing enrich uranium for its civilian nuclear reactors. That leaves open the possibility the fissile material could be diverted to covert nuclear sites to make enough highly enriched uranium to make a bomb.

The amount of fissile material Iran has is closely linked to when it can produce a weapon. Even if the country went all out with present enrichment capability, it is unlikely to have enough until 2010 at the earliest, the officials said. The State Department's Intelligence and Research office believes the earliest likely time it would have enough highly enriched uranium would be 2013. But all agencies concede Iran may not have sufficient enriched uranium until after 2015.

Iran would not be capable of technically producing and reprocessing enough plutonium for a weapon before about 2015, the report states. But ultimately it has the technical and industrial capacity to build a bomb, "if it decides to do so," the intelligence agencies found.

Estimate was delayed
This national intelligence estimate was originally due in the spring of 2007 but was delayed because the agencies wanted more confidence their findings were accurate, given the problems with a 2002 intelligence estimate of Iraq's weapons of mass destruction program. They also got a late influx of new data that caused changes in their findings.

"There was a very rigorous scrub using all the trade craft available, using the lessons of 2002," a senior official said.

At the White House, National Security Adviser Stephen Hadley said the findings confirm that the risk of Iran acquiring a nuclear weapon remains "a serious problem."

"The estimate offers grounds for hope that the problem can be solved diplomatically without the use of force as the Administration has been trying to do," Hadley said. "And it suggests that the president has the right strategy: intensified international pressure along with a willingness to negotiate a solution that serves Iranian interests, while ensuring that the world will never have to face a nuclear armed Iran."

Hadley added: "The bottom line is this: for that strategy to succeed, the international community has to turn up the pressure on Iran with diplomatic isolation, United Nations sanctions, and with other financial pressure and Iran has to decide it wants to negotiate a solution."

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