Sources in the U.S. intelligence community that Iran was rapidly advancing in its uranium enrichment program.

U.S. officials said most of the intelligence community, particularly the Defense Intelligence Agency, has concluded that Iran was succeeding in assembling and installing gas centrifuges at the uranium enrichment facility at Natanz. They said the pace of the work has been slower than promised by Tehran, but much faster than expected by the intelligence community.

“They are moving steadily and gaining experience and knowledge all the time,” an official said. “This will allow them to increasingly accelerate the uranium enrichment project.”

American officials said Iran has installed more than 1,000 centrifuges at Natanz. They said the centrifuges were being tested in an underground facility to determine their suitability for uranium enrichment.

The Tehran regime has vowed to install 3,000 centrifuges this month. Officials said about half of the centrifuges have been installed, both in the underground and formal project at Natanz. Iran has provided limited access to the formal uranium enrichment project, where it operates at least 320 such centrifuges.

“This kind of expansion of Iran’s centrifuge capability is why we went to the U.N. Security Council and pushed for a stronger resolution and stronger sanctions,” State Department spokesman Sean McCormack said.

On Tuesday, ABC News quoted U.S. sources as saying that Iran could produce enriched uranium sufficient for a nuclear weapon by 2009. The U.S. television network said that, since January, Iran has more than tripled its ability to produce enriched uranium.

American officials said that Iran would fulfill its pledge to install 3,000 centrifuges by June. They said they could not estimate how many of the machines would work.

“I think we have all been caught off guard,” said David Albright, president of the Institute for Science and International Security. “Iranian President Mahmoud Ahmadinejad said they would have these 3,000 installed by the end of May, and it appears they may actually do it.”

Iran, Russia Try To Resolve Bushehr Delay

Iran and Russia plan another round of talks to revive the nuclear reactor project at Bushehr.

Iranian officials said a Russian delegation was scheduled to arrive imminently to remove obstacles for the completion of the 1,500 megawatt Bushehr nuclear energy reactor. They said the delegation of the Russian state-owned prime contractor, Atomstroiexport, would discuss a timetable for the start of reactor operations.

“In the next two or three days, the Russians will come to Teheran to sign an agreement to solve the financial problems of Atomstroiexport,” Iranian Atomic Energy Organization Director Gholam Aghazadeh said on Tuesday.

In March, Iran relayed about $23 million to Atomstroiexport, the first complete monthly payment to the contractor since September 2006. Iran said it has already paid more than 90 percent of the $1 billion project, but Atomstroiexport has sought additional funding.

“The Russians have told us that since their company does not have money ‘you need to help us financially,'” Aghazadeh said. “A framework has been found to solve their financial problems.”

In September 2006, Russia pledged to begin initial operations at Bushehr in September 2007 and full operations two months later. Officials said this would have required the first shipment of nuclear fuel in March.

The state of the Bushehr project has not been clear. In March, Russia announced a suspension of the project and the return of many of the 2,000 Russian employees at Bushehr. But Aghazadeh said 3,000 Russians remain working at Bushehr.

“The aim of the scheduled talks is to ensure stable and sufficient financing of the Bushehr power plant construction,” Atomstroiexport spokeswoman Yesipova Yesipova said.

Iran’s failure to meet its repayment schedule led to delays, because of that, the project would probably not be completed in 2007.

“It is a good thing that our Iranian colleagues have overcome their difficulties in payments for the Bushehr plant,” Sergei Kirienko, director of Russia’s Atomic Energy Agency, Rosatom, said. “And we hope that in the future Tehran’s payments will come in accordance with the agreed schedule.”

In the first quarter of 2007, Kirienko said, Russia received $15 million from Iran, two-thirds of which arrived at the end of March. He said Tehran was committed to paying around $25 million per month to Moscow. Atomstroiexport has expressed interest in bidding for an Iranian project to construct another 10 nuclear reactors. Iran has pledged to launch a tender by August 2007 to generate 2,000 megawatts out of a proposed 20,000 megawatts of nuclear power.

“Our interpretation is that the delay of the fuel delivery is a political one,” Aghazadeh said. “But all in all they know we intend to build more nuclear power stations, and Iran is a sure market for them.”