VIENNA, May 14 — Inspectors for the International Atomic Energy Agency have concluded that Iran appears to have solved most of its technological problems and is now beginning to enrich uranium on a far larger scale than before, according to the agency’s top officials.
The findings may change the calculus of diplomacy in Europe and in Washington, which aimed to force a suspension of Iran’s enrichment activities in large part to prevent it from learning how to produce weapons-grade material.
In a short-notice inspection of Iran’s operations in the main nuclear facility at Natanz on Sunday, conducted in advance of a report to the United Nations Security Council due early next week, the inspectors found that Iranian engineers were already using roughly 1,300 centrifuges and were producing fuel suitable for nuclear reactors, according to diplomats and nuclear experts here.
Until recently, the Iranians were having difficulty keeping the delicate centrifuges spinning at the tremendous speeds necessary to make nuclear fuel and were often running them empty or not at all.
Now, those roadblocks appear to have been surmounted. “We believe they pretty much have the knowledge about how to enrich,ï¿½? said Mohammed ElBaradei, the director general of the energy agency, who clashed with the Bush administration four years ago when he declared that there was no evidence that Iraq had resumed its nuclear program. “From now on, it is simply a question of perfecting that knowledge. People will not like to hear it, but that’s a fact.ï¿½?
It is unclear whether Iran can sustain its recent progress. Major setbacks are common in uranium enrichment, and experts say it is entirely possible that miscalculation, equipment failures or sabotage — something the United States is believed to have attempted in the past — could prevent the Iranian government from reaching its goal of producing fuel on what President Mahmoud Ahmadinejad of Iran boasts is “an industrial scale.ï¿½?
The material produced so far would have to undergo further enrichment before it could be transformed into bomb-grade material. To accomplish that, Iran would likely first have to evict the I.A.E.A. inspectors, as North Korea did four years ago.
Even then, it is unclear whether the Iranians have the technology to produce a weapon small enough to fit atop their missiles, a significant engineering challenge.
While the United Nations Security Council has passed a resolution demanding that Iran suspend all of its nuclear activities, and it has twice imposed sanctions for Tehran’s refusal to do so, some European nations, and particularly Russia, have questioned whether the demand for suspension still makes sense.
The logic of demanding suspension is that it would delay the day that Iran gained the knowledge to produce its own nuclear fuel — what the Israelis used to refer to as “the point of no return.ï¿½? Those favoring unconditional engagement with Iran have argued that the current strategy is creating a stalemate that the Iranians are exploiting, allowing them to make technological leaps while the Security Council steps up sanctions.
The Bush administration, in contrast, has argued that it will never negotiate while the Iranians speed ever closer to a nuclear weapons capability, saying there has to be a standstill as long as talks proceed. In a telephone interview, R. Nicholas Burns, the undersecretary of state for policy, who is implementing the Iran strategy, said that while he has not heard about the I.A.E.A.’s newest findings, they would not affect American policy.
“We’re proceeding under the assumption that there is still time for diplomacy to work,ï¿½? he said, although he added that if the Iranians did not agree to suspend production by the time the leaders of the Group of 8 industrial nations meet next month, “we will move ahead toward a third set of sanctions.ï¿½?
Mr. ElBaradei has always been skeptical of that strategy, telling European foreign ministers that he doubts the Iranians will fully suspend their nuclear activities and that a face-saving way must be found to resolve the impasse.
“Quite clearly, suspension is a requirement by the Security Council and I would hope the Iranians would listen to the world community,ï¿½? he said. “But from a proliferation perspective, the fact of the matter is that one of the purposes of suspension — keeping them from getting the knowledge — has been overtaken by events. The focus now should be to stop them from going to industrial scale production, to allow us to do a full-court-press inspection and to be sure they remain inside the treaty.ï¿½?
The report to the Security Council next Monday is expected to say that since the Iranians stopped complying in February 2006 with an agreement on broad inspections by the agency around the country, the I.A.E.A.’s understanding of “the scope and contentï¿½? of Iran’s nuclear activities has deteriorated. I
Inspectors are concerned that Iran has declined to answer a series of questions, posed more than a year ago, about information the agency received from a Pakistani nuclear engineer, Abdul Qadeer Khan. Of particular interest is a document that shows how to design the collision of two nuclear spheres — something suitable only for producing a weapon.
The inspection conducted on Sunday took place on two hours notice, a time period so short that it appears unlikely that the Iranians could have turned on their centrifuges to impress the inspectors. According to diplomats familiar with the inspectors’ report, in addition to 1,300 working centrifuges, another 300 were being tested and appeared ready to be fed raw nuclear fuel as soon as late this week, the diplomats said. Another 300 are under construction.
“They are at the stage where they are doing one cascade a week,ï¿½? said one diplomat familiar with the analysis of Iran’s activities, who declined to be identified because of the sensitivity of the information. A “cascadeï¿½? has 164 centrifuges, and experts say that at this pace, Iran could have 3,000 centrifuges operating by June — enough to make one bomb’s worth of material every year. Tehran may, the diplomat said, be able to build an additional 5,000 centrifuges by the end of the year, for a total of 8,000.
The inspectors have tested the output and concluded that Iran is producing reactor-grade uranium, enriched to a little less than 5 percent purity. But that still worries American officials and experts here at the I.A.E.A. If Iran stores the uranium and later runs it through its centrifuges for another four or five months, it can raise the enrichment level to 90 percent — the level needed for a nuclear weapon.
In the arcane terminology of nuclear proliferation, that is known as a “breakout capability,ï¿½? the ability to throw inspectors out of the country and then produce weapons-grade fuel, as North Korea did in 2003.
Some Bush administration officials and some nuclear experts here at the I.A.E.A. and elsewhere suspect that the Iranians may not be driving for a weapon but rather for that “breakout capability,ï¿½? because that alone can serve as a nuclear deterrent. It would be a way for Iran to make clear that it could produce a bomb on short notice, without actually possessing one.
One senior European diplomat, who declined to speak for attribution, said Washington would now have to confront the question of whether it wants to keep Iran from producing any nuclear material or whether it wants to keep Tehran from gaining the ability to build a weapon on short notice.
“The key decision you have to make right now,ï¿½? the diplomat said, “is that if you don’t want the breakout scenario, you would have to freeze the Iranian program at a laboratory scale. Because if you continue this stalemate, that will bring you, eventually, to a breakout capability.ï¿½?
Those in the Bush administration who take a hard line on Iran make the opposite argument. They say that the only position that President Bush can take now, without appearing to be backing down, is to stick to the administration’s past argument that “not one centrifuge spinsï¿½? in Iran. They argue for escalating sanctions and the threat that, if diplomacy fails, the United States could take out the nuclear facilities in a military strike.
But even inside the administration, many officials, particularly in the State Department and the Pentagon, argue that military action would prompt greater chaos in the Middle East and Iranian retribution against American forces in Iraq and possibly elsewhere. Moreover, they have argued that Iran’s enrichment facilities are still at an early enough stage that a military strike would not set the country’s program back very far. Such a strike, they argue, would only make sense once large facilities have been built.
Vice President Cheney, in an interview conducted with Fox News at the end of his trip to the Mideast, said today that Iran appears “to be determined to develop the capacity to enrich uranium in order to produce nuclear weapons.ï¿½? But he issued no threats, saying simply “they ought to comply with the U.N. resolutions.ï¿½?
He noted that President Bush personally made the decision to engage in talks with Iran, at the ambassadorial level, about Iran’s activities in Iraq. But those talks are supposed to specifically exclude the nuclear dispute.