The head of the International Atomic Energy Agency warned Monday that he cannot determine whether Iran is hiding some nuclear activities, comments that appeared to reflect a high level of frustration with stonewalling of his investigators.
IAEA head Mohamed ElBaradei said Iran's stonewalling of his agency was a "serious concern."
"Iran needs to give the agency substantive information" to clear up suspicions, he said at the start of a 35-nation, semi-annual IAEA board meeting, in comments made available to reporters.
Diplomats at the gathering described ElBaradei's comments as unusually blunt.
Israeli officials welcomed the comments, saying that ElBaradei said in plain English what the IAEA report on Iran issued last week said in technical jargon.
Foreign Ministry spokesman Yigal Palmor said the statement was significant, because it showed that it was not just the West that was "jumping on Iran," as some have accused.
Palmor said Israel was not at all surprised by the content of ElBaradei's statement, and said it could be a useful lever to get the international community to work more intently to get Iran to halt its nuclear program.
ElBaradei rejected the 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."
"We need, however, to make use of all relevant information to be able to confirm that no nuclear material is being used for nuclear weapons purposes," he said, urging Iran to "implement all measures required to build confidence in the exclusively peaceful nature of its nuclear program at the earliest possible date."
If Teheran 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.
A senior Iranian envoy accused the United States of trying to use the IAEA as a tool in Washington's confrontation with Teheran. Iran, he said, had demonstrated full cooperation with the agency. Allegations of nuclear weapons work by Teheran were based on forged documents and the issue was closed, the envoy said.
With time running out before Teheran develops potential nuclear weapons capacity, some worry that Israel or the US might resort to military strikes if they believe all diplomatic options have been exhausted.
And with Teheran showing no signs of giving up uranium enrichment or heeding other international demands, the diplomatic window appears to be closing.
Outside the meeting, an indignant Ali Ashgar Soltanieh, the chief Iranian delegate to the IAEA, rejected suggestions his country was hiding something, and accused Washington of hijacking the agency for an anti-Iran campaign.
"The international community and all member states of the IAEA are frustrated with this kind of United States action in the IAEA," he told reporters. "The Americans are every day isolating themselves.
"Iran is of course very advanced in missile activities and technology," he said. "But there is no activity at all related to nuclear weapons."
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.
According to Israeli estimates the Islamic Republic may have enough nuclear material to make its first bomb within a year, with Brig.-Gen. Yossi Baidatz telling the cabinet Sunday that Iran already had between one-third to one-half of the enriched material needed to make a bomb. The US estimates Teheran is at least two years away from being able to build its first bomb.
Physicist and former UN nuclear inspector David Albright says Teheran could reach weapons capacity in as little as six months through uranium enrichment.
An IAEA report drawn up for the IAEA board meeting says that Teheran 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 closely tracks suspect secret proliferators, says he has also been able to extrapolate other information from the report that is less obvious but of at least equal concern.
Iran, he says, 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, he says, "now appear to be running at approximately 85 percent of their stated target capacity, a significant increase over previous rates."
He says that means they can produce more enriched uranium faster. And while the IAEA says that the machines have spewed out only low-enriched material suitable solely for nuclear fuel, 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 1,000 pounds of low-enriched uranium, said the report - close to what Albright says is the 1,500-pound minimum needed to produce the 45-60 pounds 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 "several months," he says.
But that work could be done secretly and consecutively with the last stages of weapons-grade enrichment. With Iran limiting access of IAEA inspectors to facilities it has declared to the agency, the UN nuclear monitor is blind-sided in efforts to establish whether such covert atomic work is going on.
