The IAEA report left hanging the question of whether Israel would ratchet up the pressure on Washington and its allies to show that they can deal with the threat of a nuclear-armed Iran diplomatically. Israeli officials have hinted, but never explicitly threatened, that they would take military action if diplomacy fails and Iran is close to weapons capability.

 

Administration officials have argued that the combination of the sanctions they expect to come out of the Security Council, along with other sanctions imposed by the United States and its European allies, may change Iran’s calculus. Sanger and Broad write Many inside and outside the administration are highly skeptical.

It has been four years since the Security Council first demanded that Iran cease all enrichment of uranium, citing its efforts to hide its activities and deceive inspectors. The country has openly defied those resolutions, telling inspectors that those demands — along with calls to allow inspectors to visit a series of facilities that could be useful in energy or weapons production — had been “issued illegally and have no legal basis.”

The inspectors reported Monday that Iran has now produced more than 5,300 pounds of low-enriched uranium, all of which would have to undergo further enrichment before it could be converted to bomb fuel.

The inspectors reported that Iran had expanded work at its sprawling Natanz site in the desert, where it is raising the level of uranium enrichment up to 20 percent — the level needed for the Tehran Research Reactor, which produces medical isotopes for cancer patients. But it is unclear why Iran is making that investment if it plans to obtain the fuel for the reactor from abroad, as it would under its new agreement with Turkey and Brazil.

Until recently, all of Iran’s uranium had been enriched to only 4 percent, the level needed to run nuclear power reactors. While increasing that to 20 percent purity does not allow Iran to build a weapon, it gets the country closer to that goal. The inspectors reported that Iran had installed a second group of centrifuges — machines that spin incredibly fast to enrich, or purify, uranium for use in bombs or reactors — which could improve its production of the 20 percent fuel.

The inspectors also noted that the agency had finally succeeded in setting up a good monitoring system for the 20 percent work after a rocky start in February, when Iran began raising the enrichment levels. “A new safeguards approach is now being implemented,” the report said.

The report called the equipment upgrades and the continuing enrichment “contrary to the relevant resolutions of the I.A.E.A.’s Board of Governors and the Security Council.” Both have called on Iran to cease its uranium enrichment because of outstanding questions about Tehran’s intentions. The sanctions, if passed, are intended to compel Iran to comply with that demand by the Security Council.

Last fall, President Obama, along with the leaders of Britain and France, denounced Iran for secretly building a second enrichment plant near the city of Qum, without alerting inspectors until just before the three leaders’ countries announced they had discovered the facility. But curiously, the report suggested that now, with its existence revealed, Iran might be losing interest in it. The report said that Iran had installed no centrifuges in the half-built enrichment facility, which is located inside a mountain near a military base.

Iran has sought to locate many of its nuclear facilities in underground sites so as to lessen their vulnerability to aerial attacks (see William J. Broad, “Iran Shielding Its Nuclear Efforts in Maze of Tunnels,” 5 January 2010 New York Times). In the new report, the inspectors said that the Iranians disclosed that a new analytical laboratory planned for construction amid a warren of tunnels at Isfahan “would have the same functions as the existing” unprotected laboratory there.

The report quoted an Iranian letter as saying the second, underground laboratory was needed “to meet security measures.”