In a 2007 National Intelligence Estimate, the United States Intelligence Community assessed that Iran had ended all "nuclear weapon design and weaponization work" in 2003.[11] In 2012, U.S. intelligence agencies reported that Iran was pursuing research that could enable it to produce nuclear weapons, but was not attempting to do so.[12]
In November 2011, the International Atomic Energy Agency (IAEA) Board of Governors criticized Iran after an IAEA report concluded that before 2003 Iran likely had undertaken research and experiments geared to developing a nuclear weapons capability.[13] The IAEA report details allegations that Iran conducted studies related to nuclear weapons design, including detonator development, the multiple-point initiation of high explosives, and experiments involving nuclear payload integration into a missile delivery vehicle.[14] A number of Western nuclear experts have stated there was very little new in the report, that it primarily concerned Iranian activities prior to 2003,[15] and that media reports exaggerated its significance.[16] Iran threatened to reduce its cooperation with the IAEA