VIENNA, Austria - The head of the UN's nuclear watchdog says the agency it unable to tell if Iran is hiding secret nuclear activities.
The remarks by Mohamed ElBaradei appear to reflect frustration within the International Atomic Energy Agency of what it sees as stonewalling by the Iranians.
ElBaradei told the 35-country IAEA board at a meeting Monday that "Iran needs to give the agency substantive information" to clear up suspicious over its nuclear program.
ElBaradei rejected an Iranian suggestion that the IAEA probe could expose non-nuclear military secrets, saying the IAEA "does not in any way seek to pry into Iran's conventional or missile-related military activities."
Diplomats at the gathering described ElBaradei's comments, which were made available to reporters, as unusually blunt.
Ali Ashgar Soltanieh, the chief Iranian delegate to the IAEA, rejected the criticism, saying the IAEA is being hijacked by the United States as part of Washington's anti-Iran campaign.
However, ElBaradei said the IAEA needs "all relevant information to be able to confirm that no nuclear material is being used for nuclear weapons purposes."
He urged Iran to "implement all measures required to build confidence in the exclusively peaceful nature of its nuclear program at the earliest possible date."
If Tehran fails to do so, the IAEA "will not be able to provide credible assurances about the absence of undeclared nuclear material and activities in Iran," he said.
Israel and the United States have both hinted at possible military strikes if they believe all diplomatic options have been exhausted to halt Iran's alleged nuclear weapons program.
Iran insists it program is peaceful and points out that the uranium enrichment activities the West wants it to give up are protected under the Nuclear Non-Proliferation Treaty.
The U.S. and many of its allies insists Iran cannot be trusted with such technology.
Ahead of the meeting, Iranian President Mahmoud Ahmadinejad declared that Iran's military will "break the hand" of anyone targeting the country's nuclear facilities.
Israel contends Iran could have enough nuclear material to make its first bomb within a year, while the United States estimates Tehran is at least two years away.
Former UN nuclear inspector David Albright claims Tehran could reach weapons capacity in as little as six months through uranium enrichment.
An report drawn up for the IAEA board meeting said that Tehran has increased the number of centrifuges used to process uranium to nearly 4,000 from 3,000 just a few months ago.
But Albright, whose Washington-based Institute for Science and International Security tracks what it calls secret proliferators, says Iran has managed to iron out most of the bugs in the intensely complicated process of enrichment that often saw the centrifuges breaking down.
The machines, "now appear to be running at approximately 85 per cent of their stated target capacity, a significant increase over previous rates," he said.
That, he says means, they can produce more enriched uranium faster.
The IAEA says that the machines have spewed out only low-enriched material suitable solely for nuclear fuel. But Albright claims producing enough of that can make it easy to "break out" quickly by reprocessing it to weapons-grade uranium suitable for the fissile core of a warhead.
To date, Iran has produced nearly 500 kilograms of low-enriched uranium, said the report - close to what Albright says is the 700-kilogram minimum needed to produce the 20 to 25 kilograms needed for a simple nuclear bomb under optimal conditions.
And with Iran's centrifuges running ever more smoothly, it "is progressing toward this capability and can be expected to reach it in six months to two years," says Albright.
Additional work -- making a crude bomb to contain the uranium -- would take no more than a "several months," he said.
