Iran is a signatory to the Nuclear Non-proliferation Treaty, maintaining its nuclear program is for peaceful purposes only. The U.N. Security Council in July expressed doubt, however, over the "uniquely civilian character" of Iran's nuclear work.
Yukiya Amano, director general of the International Atomic Energy Agency, said it's essential for Iran to cooperate with inspectors.
"Given the nature and extent of credible information available to the agency about possible military dimensions to Iran's nuclear program, it remains essential and urgent for Iran to engage with us on the substance of our concerns," he said in a statement Monday.
U.N. nuclear inspectors were denied access to the Parchin military complex last year. Amano said inspectors were concerned about the site, though Iran said inspectors had failed to convince it a visit to the complex was necessary.
Amano said the IAEA doesn't have the assurances from Iran it needs to allay its nuclear concerns.
"The agency, therefore, cannot conclude that all nuclear material in Iran is in peaceful activities," he said.
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