"To date there is no evidence that the previously undeclared nuclear material and activities referred to (in the report) were related to a nuclear weapons program," the report said, according to a text of the confidential document read to AFP.

"However, given Iran's past pattern of concealment it will take some time before the agency is able to conclude that Iran's nuclear program is exclusively for peaceful purposes."

The report was written by IAEA chief Mohamed ElBaradei ahead of an IAEA meeting next week that will decide whether Iran should be cited for hiding an alleged nuclear weapons program.

A ruling of Iranian non-compliance with nuclear Non-Proliferation Treaty (NPT) safeguards agreements could lead to UN sanctions against Iran.

The report said "the agency must have a particulary robust verification system in place. An additional protocol (on wider inspections) is indispensable for such a system, coupled with a policy of full transparency and openness."

Iran handed the UN nuclear watchdog Monday a letter agreeing to tougher inspections of its nuclear program and informed the agency it was suspending the enrichment of uranium, the Iranian ambassador to the IAEA told AFP.

Ali Akbar Salehi said he had "handed over the letter" to ElBaradei.

WAR.WIRE