The IAEA report said that Iranian scientists launched an effort known as Project 5 that was aimed at producing “a source of uranium suitable for use in an undisclosed enrichment program. The product of this program would be converted into metal for use in a new warhead which was the subject” of studies on designing a missile “re-entry vehicle.”

“The agency has serious concerns about the military dimensions to Iran’s nuclear program,” said the IAEA report. “After assessing carefully and critically the extensive information available to it, the agency finds the information to be, overall, credible.”

Because of Tehran’s refusal since 2008 to cooperate in the IAEA investigation, the agency “is unable to provide credible assurance about the absence of undeclared nuclear material and activities in Iran, and therefore to conclude that all nuclear material in Iran is for peaceful activities,” said the report.

The IAEA urged Iran “to engage substantively with the agency without delay for the purpose of providing clarifications regarding possible military dimensions to Iran’s nuclear program.”

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