While international inspectors have never found concrete evidence linking Iran’s nuclear program to weapons development, Iran’s concealment of its program--like the partially constructed enrichment facility near Qom, which Western officials say was under construction for years before Iran’s disclosure in the fall of 2009 -- has fed concerns . In a June 2003 report (PDF) , IAEA inspectors concluded that Iran had failed to meet obligations under its Safeguards Agreement signed in 1974. Failures included withholding construction and design details of new facilities, and not reporting processed and imported uranium. Some undeclared shipments dated to 1991, the IAEA said.
Nevertheless, throughout the late 1990s and the early 2000s, the United States claimed that Iran maintained an active program for the development and production of chemical weapons. This program was alleged to include stockpiles of blood , blister , choking , and possibly nerve agents , although . intelligence agencies did not publicly provide evidence for these allegations.  Since 2003, the . intelligence community has substantially downgraded its public assessments of Iranian chemical warfare capabilities. In its most recent unclassified report to Congress on the subject, the Director of National Intelligence asserted that Iran "maintains the capability to produce chemical warfare (CW) agents and conducts research that may have offensive applications."  Iran denies producing or possessing chemical weapons in violation of its treaty obligations.
Iran, the United States and the five other countries agree to a four-month extension of the negotiations, giving them more time to try to bridge a major difference over whether the country will be forced to dismantle parts of its nuclear infrastructure, according to senior Western diplomats involved in the talks. Iran Altering Arak Reactor in Bid for Nuclear Deal Atomic power engineers in Iran start redesigning a partly constructed reactor in Arak to limit the amount of plutonium it produces, Ali Akbar Salehi, the director of the Atomic Energy Organization of Iran, says, expressing hope that the change will help alleviate Western objections that the plutonium can be used in weapons. Role for Russia Gives Iran Talks a Possible Boost Iran tentatively agrees to ship much of its huge stockpile of uranium to Russia for conversion into specialized fuel rods for the Bushehr nuclear power plant, Iran’s only commercial reactor. The agreement is potentially a major breakthrough in talks that have until now been deadlocked.