Inspectors for the International Atomic Energy Agency have concluded that Iran appears to have solved most of its technological problems and is 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 in large part to prevent it from learning how to produce weapons-grade material.
In a short-notice inspection of Iran's main nuclear plant at Natanz on Sunday, conducted in advance of a report to the U.N. Security Council early next week, 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 often were running them empty, or not at all.
Those roadblocks appear to have been surmounted. "We believe they pretty much have the knowledge about how to enrich," said Mohamed 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."
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 could prevent the Iranian government from reaching its goal of producing fuel on what President Mahmoud Ahmadinejad boasts is "an industrial scale." The material produced so far would have to undergo further enrichment before it could be transformed into bomb-grade material, and to accomplish that Iran would probably first have to evict the IAEA inspectors, as North Korea did four years ago.
Even then it is unclear whether the Iranians would have the technology to produce a weapon small enough to fit atop their missiles, a significant engineering challenge.
Iran says its nuclear program is intended to produce energy, not weapons..
While the U.N. Security Council has passed a resolution demanding that Iran suspend all of its nuclear activities, and twice imposed sanctions for its 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 was 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." 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.