Obama Calls for Patience in Iran Talks

President Obama made a vigorous appeal to Congress on Thursday to give breathing space to his efforts to forge a nuclear deal with Iran, and the prospects for an interim agreement may have improved with the release of a report by international inspectors who said that for the first time in years, they saw evidence that the Iranians have put the brakes on their nuclear expansion.

The inspectors, from the International Atomic Energy Agency, said that very few new advanced centrifuges had been installed since President Hassan Rouhani of Iran took office in June, promising a new start with the West, and that little significant progress has been made on the construction of a new nuclear reactor, which became a point of contention in negotiations in Geneva last week.

The slowdown, according to diplomats familiar with the Iranian work, was clearly political, not driven by technical problems. But it was also easily reversible, suggesting that Iran was waiting to see what kind of relief from sanctions it could obtain from the West in the negotiations.

The report was immediately seized on by advocates and critics of an agreement that was almost signed in Geneva.

Administration officials said Iran’s restraint was the latest in a series of signals by Mr. Rouhani that he was an agent of change, and that it was an answer to skeptics who have said the Iranian leader was all talk and no action.

But critics in Congress and overseas dismissed the report, saying that Iran had not removed any centrifuges and continued to enrich uranium at a steady rate. Prime Minister Benjamin Netanyahu of Israel, one of the most vocal critics of a deal, said the only reason Iran had not expanded its enrichment capability was that “they don’t need to.”

For Mr. Obama, who has been fending off accusations that the American negotiators were giving away too much to Iran in return for concessions that critics said would scarcely slow its march to nuclear capability, the findings could fortify his argument that the Senate should hold off on new sanctions to avoid derailing the talks.

“Let’s test how willing they are to actually resolve this diplomatically and peacefully,” Mr. Obama said at a White House news conference. “We will have lost nothing if at the end of the day it turns out that they are not prepared to provide the international community the hard proof and assurances necessary for us to know that they’re not pursuing a nuclear weapon.”

The confidential report was released to the nuclear agency’s member states just minutes before Mr. Obama spoke, and he did not mention the findings. But the president made a strong case for diplomacy, trying to quell an effort in Congress to ramp up sanctions against Iran rather than modestly ease them, in return for a six-month halt in the progress of the nuclear program.

Negotiators plan to meet again next week in Geneva, after failing to reach an interim deal because of what Secretary of State John Kerry has described as a difference in only four or five phrases. The prospect that a deal could be reached soon has provoked a storm of protest from Israel and criticism from Republicans and some Democrats.

The I.A.E.A. report does not show anything close to an across-the-board freeze or rollback in Iran’s program. Iran continues to produce low-enriched uranium around the pace it has in the past. But inspectors, who completed their last visit to Iran just days ago, said that no more new, highly efficient centrifuges that the country has invested heavily in building were installed at its two main nuclear sites. Those centrifuges, called the IR-2, were particularly worrisome because they would shorten Iran’s “breakout time” to build a weapon, if they were operating.

The report said that Iran, at its Fordo plant near the city of Qum, had not put more of its existing 2,710 centrifuges into operation. Only 696 of the installed machines, all of the older IR-1 model, are actually enriching uranium — well below the plant’s capacity.

Iran’s stockpile of its most worrisome category of uranium — enriched to nearly 20 percent, close to bomb grade — increased only modestly. Since the last quarterly accounting, Iran has added roughly 10 kilograms, or about 22 pounds, of uranium enriched to 20 percent purity to its stockpile, bringing its total of the medium-enriched material to roughly 196 kilograms, or about 432 pounds. Iran is turning most of that uranium into fuel for reactors, which diminishes its threat as a bomb fuel.

The report also found that Iran had performed only minor work on the heavy-water reactor at Arak, a facility that has raised alarm because it could eventually produce plutonium, giving Iran a second source of bomb fuel.

Nader Karimi Joni, a political analyst close to the Rouhani administration, said, “It is fair to say that Iran is showing good will, just like the European Union and the United States have done.”

Still, experts on Iran cautioned against imputing a political motive to what is fundamentally a technical decision.

“It is difficult to decipher political motivation from technological pace,” said Ray Takeyh, a senior fellow at the Council on Foreign Relations. “Having said that, it may be a signal of some sort. Alternatively, Iran has been having difficulty with its machines, so it may be trying to perfect their design and operation. Or a combination of all the above.”

The lack of certainty about Iran’s motives lends itself to widely conflicting interpretations of the report’s findings.

“They’ve got enough facilities, enough centrifuges, to develop and to complete the fissile material which is at the core of an atomic bomb,” Mr. Netanyahu said Thursday.

On Capitol Hill, aides to Republican and Democratic senators dismissed the report. “It simply confirms the concerns that senators already have: There have been no centrifuges removed,” said one. Another added, “They’re closing it down in the morning and opening it up in the afternoon.”

On Wednesday, Mr. Kerry and Vice President Joseph R. Biden Jr. met with Senate leaders, who are considering a new set of sanctions that aim to drive Iran’s oil exports to zero. But there was little evidence that the senators were persuaded to delay action.

Aides said Republican senators were likely to attach the sanctions bill as an amendment to the National Defense Authorization Act, which funds the military. But with Thanksgiving break looming, they said, the Senate was unlikely to vote on it before the next round of talks, which begin on Thursday.

At the White House, Mr. Obama disputed critics who said that the United States and its negotiating partners were preparing to give up too much, saying that under the interim deal being discussed, the United States would offer only “very modest relief at the margins of the sanctions that we’ve set up.”

Mr. Obama said an interim deal would halt Iran’s program; dilute its stockpile of highly enriched uranium, which can be quickly converted to weapons-grade fuel; and subject Iran’s facilities to more vigorous inspections. That would give both sides the breathing space to conduct talks on a comprehensive deal.

And if those talks fail, the president said, Congress can easily ramp up the sanctions again.