U.S., Iran Explore Option of 10-Year Nuclear Freeze

Compromise could see 12-month ‘breakout’ period for a decade, then allow Iran to build capacity.

The U.S. and Iran are exploring a nuclear deal that would keep Tehran from amassing enough material to make a bomb for at least a decade, but could then allow it to gradually build up its capabilities again.

Such a deal would represent a significant compromise by the U.S., which had sought to restrain Tehran’s nuclear activities for as long as 20 years. Tehran has insisted on no more than a 10-year freeze.

The possible compromise on the table appears closer to Tehran’s timeline. While it would add some years in which the Iranian nuclear program continues to be closely monitored and constrained, Iran would be able to increase its capacity to enrich uranium, and thus get closer to bomb-making capability again.

Critics in Congress and in Israel quickly attacked the prospect of a 10-year time frame as inadequate.

After four days of talks in Geneva, a senior U.S. official on Monday said there had been welcome progress toward a deal, while giving no specifics about its timeline.

The U.S. has been pushing for a freeze that would establish a period of time during which Iran would remain at least 12 months away from being able to fuel an atomic bomb—a so-called breakout period. Asked if Iran must accept that breakout period through the lifetime of an accord, the person signaled that may not be necessary.

“We have always said that we would have a one-year breakout time for a double-digit number of years and that remains the case,” the official said.

That suggests a period of as little as 10 years. When pressed, the official declined to elaborate.

Such a compromise could allow Iran to portray the major restrictions on its nuclear program at home as lasting only 10 years—an upper limit Iranian officials have mentioned before. Iran says its nuclear program is a purely civilian, peaceful one.

It also could break the impasse over how many centrifuges—machines for enriching uranium—Tehran would be allowed under a deal. If Iran can expand its activities, it could start with fewer centrifuges and then be allowed to operate more over time.

The Obama administration maintains that it doesn’t need congressional approval for the deal because it isn’t a treaty, although Congress would have to vote to lift some of the sanctions it has imposed on Iran over the years.

Sen. Bob Corker (R., Tenn.) said in an interview that a 10-year time frame wasn’t long enough to truly curb Tehran’s nuclear ambitions.

The Israeli government has been a leading critic of the talks, which Prime Minister Benjamin Netanyahu on Sunday warned were destined to end in a “dangerous” deal.

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