Iran conducted preliminary work "relevant" to building a nuclear bomb, but the efforts never went beyond planning and testing basic components, according to a much anticipated report from the United Nations nuclear watchdog, which said there was no evidence such activities continued past 2009.

"The agency assesses that a range of activities relevant to the development of a nuclear explosive device were conducted in Iran prior to the end of 2003 as a coordinated effort, and some activities took place after 2003," said the International Atomic Energy Agency in a report shared today that concluded its lengthy probe into the possible military dimensions of Iran's nuclear program.

However, the activities "did not advance beyond feasibility and scientific studies, and the acquisition of certain relevant technical competences and capabilities," added the agency, reported AFP.

The report noted the existence of an "organized structure" prior to 2003 "suitable for the coordination of a range of activities relevant to the development of a nuclear explosive device," the development of detonators "relevant to a nuclear explosive device" and work on a separate explosives initiator that had "characteristics relevant to a nuclear explosive device." Environmental samples from one particular site contradict Iranian claims that the site was used only for non-nuclear purposes, a strong indication that Iran conducted tests of explosives designed to set off a nuclear charge, according to the Associated Press. The report said some of the work may have been for civilian or conventional military purposes.

Iran also failed to provide new information on some IAEA queries going back to 2011, regarding work that the IAEA said seemed to have no purpose but to design nuclear weapons, according to the AP.

The IAEA said its inspectors "found no credible indications of the diversion of nuclear material in connection with the possible military dimensions to Iran's nuclear program," nor are there "credible indications of activities in Iran relevant to the development of a nuclear explosive device after 2009."

The findings come five months after Iran and six world powers entered into a landmark deal that would lift international sanctions on Iran in exchange for placing verifiable limits on its nuclear program to prevent it from developing a nuclear weapon.

The IAEA report was a condition of that deal, and pending its approval by the IAEA's board of governors at a Dec. 15 meeting, the report will end the inquiry into weather Iran developed nuclear weapons and move Tehran a step closer to sanctions relief, according to Bloomberg.

If the report is approved by the board of governors, Iran will be allowed to accelerate implementation of the agreement by exporting more than 17,636 pounds of enriched uranium. Tehran will also move forward with upholding its end of the deal by shutting down thousands of centrifuges and redesigning its Arak heavy water reactor, which would prevent it from producing weapons-grade plutonium.

"The final report of IAEA shows no evidence of a nuclear weapons program or diversion of nuclear material in Iran has been found. Now we can say all measures regarding past issues have been completely resolved and the issue" of possible military dimensions is now finished, said Iran's Deputy Foreign Minister Abbas Araghchi, reported Fox News, citing Iran's Tasnim News.

The U.S State Department responded to the report by saying Iran had cooperated adequately with investigators and that it was ready to take the next step in implementing the deal.

"The IAEA report is consistent with what the United States has long assessed with high confidence... Iran had a nuclear weapons program that was halted in 2003," said State Department spokesman Mark Toner.

Once the deal is implemented, which could take months, the world "will have assurance that these kinds of past activities cannot occur again," said Toner, according to the Hill. "We'll have that ability to go in and see what's going on, so if we do see a recurrence of this past activity, we'll be able to immediately address it."