proposed legislation to address Iran’s missile program and proxy support “after such time that all sides return to their commitments”
under the nuclear accord.

Iran’s leaders have warned that expanding the accord is a nonstarter, and European diplomats worry that broaching it in the delicate negotiations will scuttle the entire effort.

“Once we do the first step, then we can continue, or start talking about other pending issues,” Mr. Borrell said at the Atlantic Council, a policy center. “But if you start talking about the pending issues in the beginning, you will never restart.”

Trita Parsi, the founder of the National Iranian American Council and executive vice president of the Quincy Institute, a policy center that advocates military restraint, said both Iran and the United States would “have to swallow some pride and pay a political cost” if negotiations were to restart.

“And the longer they wait, the higher that cost will be,” Mr. Parsi wrote in an analysis published on Feb. 28.

Iran’s latest breach of the nuclear deal came on Feb. 23, when Tehran formally prohibited the International Atomic Energy Agency from conducting snap inspections of at least some Iranian nuclear sites.

Mr. Grossi rushed in to negotiate a three-month stopgap, during which Iran will give inspectors some access to its sites as diplomats try to rekindle negotiations. After Mr. Grossi’s second meeting with Iranian officials in two weeks, European diplomats announced they would hold off, “for now,” on formally rebuking Iran’s refusal to allow snap inspections.

Mr. Blinken’s demand for the release of Americans being held in Iran by opening the door to direct negotiations with the United States on a prisoner exchange. At least four American dual citizens are being held by Iran, which has a long history of detaining foreigners and dual citizens on bogus charges of espionage and swapping them for Iranians incarcerated abroad.

An Iranian government spokesman, Ali Rabiei, said the impasse over the nuclear accord should not delay a prisoner swap. “We can discuss all the prisoners at one time and resolve this issue,” Mr. Rabiei told journalists in Tehran.

Last month, the United States lifted travel restrictions on Iranian officials visiting the United Nations headquarters in New York, and dropped its demand that the United Nations Security Council enforce international sanctions against Iran. Both were presented to Tehran as good-faith efforts.

Despite the impasse, American and European diplomats said informal talks could begin in coming weeks. When they do, it is expected that the United States and Iran could agree to take simultaneous steps toward coming back into compliance with the 2015 accord.

Farnaz Fassihi contributed reporting from New York.

View Source