Iran has been working toward building a nuclear weapon since 2003, according to a report released by the International Atomic Energy Agency and obtained by Haaretz on Tuesday.
The report, which was handed over to the 35-member states of the IAEA Board of Governors, details a series of tests, acquisition of materials, and technology that suggests Iran has continuously worked to produce a nuclear weapon since 2003.
A diplomatic source in Vienna told Haaretz that this is "the most damning report ever published by the IAEA and the conclusion arising from it is one: Iran is working to acquire a nuclear weapon."
"The agency has serious concerns regarding possible military dimensions to Iran's nuclear program," the IAEA said in the report, which included a 13-page annex with key technical descriptions of research.
Citing "credible" information, the Vienna-based agency said the data "indicates that Iran has carried out activities relevant to the development of a nuclear explosive device."
It added: "The information also indicates that prior to the end of 2003, these activities took place under a structured program, and that some activities may still be ongoing."
U.S. spy services estimated in 2007 that Iran had halted outright "weaponization" research four years previously, but also that the Islamic Republic was continuing efforts to master technology usable in nuclear explosives.
The IAEA report included information from both before and after 2003.
It expressed "particular concern" about information provided by two member states that Iran had carried out computer modeling studies linked to nuclear weapons in 2008-09.
"The application of such studies to anything other than a nuclear explosive is unclear to the agency," the IAEA said.
The information also indicated that Iran had built a large explosives vessel at the Parchin military complex southeast of Tehran in which to conduct hydrodynamic experiments, which are "strong indicators of possible weapon development."
For several years the IAEA has been investigating Western intelligence reports indicating that Iran has coordinated efforts to process uranium, test high explosives and revamp a ballistic missile cone to accommodate a nuclear warhead.
Iran, the world's No. 5 oil exporter, insists that its program to enrich uranium is for a future network of nuclear power stations to provide electricity for a rapidly growing population, so that it can export more of its oil and gas.
But Tehran's history of hiding sensitive nuclear activity from the IAEA, continued restrictions on IAEA access and its refusal to suspend enrichment -- which can yield fuel for atom bombs -- have drawn four rounds of UN sanctions, as well as separate punitive steps by the United States and European Union.
IAEA officials have often complained that Iran has refused, for at least three years, to seriously answer the agency's questions about accusations of illicit nuclear activity.