I can only go by what the IAEA Report on Iran, with date 8 November 2011, says.
"A Look At The IAEA's Damning Nuclear Report On Iran"
Skipping the details about enrichment, heavy water, and fuel fabrication, we'll highlight the Possible Military Dimensions found in the International Atomic Energy's November 8 report on Iran.
Iran agreed to provide the IAEA "access without delay" to all nuclear sites, since August 2008, Tehran has not "engaged with the [IAEA] in any substantative way on this matter."
IRAN HAS carried out the following acts to produce a nuclear weapon:
Successful efforts to obtain nuclear military equipment
Tried to find undisclosed ways to develop nuclear weapons
Attempted to buy nuclear weapons, development information, and documentation from outside sources, using a "clandestine, nuclear supply network."
Worked on developing an "indigenous" nuclear weapons and components
The above activities took place since 2003 and are believed to be ongoing.
Here is the the official document:
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