The director-general of the UN nuclear agency said today that Iran had demonstrated "greater transparency" lately.
But Yukiya Amano, opening a weeklong meeting of the IAEA board of governors in Vienna, said Tehran was "not providing the necessary cooperation" to be able to conclude all its activities were peaceful, as the Islamic republic says.
"The agency is increasingly concerned about the possible existence in Iran of past or current undisclosed nuclear-related activities involving military related organizations," he said, "including activities related to the development of a nuclear payload for a missile, about which the agency continues to receive new information."
The UN Security Council has slapped four rounds of sanctions on Iran for its refusal to suspend uranium-enrichment activities, a process which can be used in a nuclear warhead.
On Syria, Amano reiterated that, despite Damascus's denials, a target hit in 2007 by Israeli warplanes was a nearly completed nuclear reactor meant to produce plutonium, which can be used to arm nuclear warheads.
He also announced that his staff would meet with Syrian officials next month to work out an "action plan" allowing Damascus to make good on promises to present new information on the site in its attempts to prove that the structure was not a nuclear military facility.
compiled from agency reports