By David Blair, Diplomatic Correspondent
Iran halted its nuclear weapons programme four years ago and may be less determined to acquire an atomic bomb than was previously thought, America's intelligence agencies said today.
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A newly declassified "National Intelligence Estimate", representing the considered judgment of all 16 US spy agencies, plays down Teheran's nuclear ambitions and says that Iran may be eight years away from mastering the technology needed to build a Bomb.
Under the heading "Key Judgments", the document says: "We judge with high confidence that in the fall of 2003, Teheran halted its nuclear weapons programme."
This freeze came when Iran stopped enriching uranium and signed an "Additional Protocol" giving more powers to inspectors from the International Atomic Energy Agency.
The combined effect of these two agreements, reached after a diplomatic drive led by Britain, France and Germany, was to render it extremely difficult for Iran to build a nuclear bomb.
In effect, American intelligence believes that Teheran's regime decided to put the entire programme on hold.
Yet these deals collapsed after President Mahmoud Ahmadinejad won power in 2005.
Even so, America's intelligence agencies "assess with moderate confidence" that "Teheran had not restarted its nuclear weapons programme as of mid-2007".
They add: "But we do not know whether it currently intends to develop nuclear weapons."
Instead, US intelligence believes "with moderate-to-high confidence" that "Teheran at a minimum is keeping open the option to develop nuclear weapons".
As for Iran's intentions, the intelligence estimate notes that Teheran's decision to freeze its bomb programme "suggests it is less determined to develop nuclear weapons than we have been judging since 2005.
"Our assessment that the programme probably was halted primarily in response to international pressure suggests Iran may be more vulnerable to influence on the issue than we judged previously".
Iran is presently enriching uranium inside the underground nuclear plant in Natanz.
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This highly sensitive procedure – which breaches three United Nations Resolutions – could be used for either civilian or military purposes.
If uranium is enriched to 4.5 per cent purity, it can be used to generate electricity in power stations.
But if Iran chooses to enrich it to 87.5 per cent purity, the uranium reaches weapons grade and become the key ingredient for a bomb.
America's intelligence agencies believe that Iran will not reach this threshold until the period between 2010 and 2015. There is a "possibility that this capability may not be attained until after 2015".
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