Negotiators work to bring U.S. back to nuclear pact

VIENNA — World powers held a fourth round of highlevel talks Friday in Austria aimed at bringing the United States back into the nuclear deal with Iran, with both sides signaling a willingness to work out the major stumbling blocks.

The talks began in early April and Russian delegate Mikhail Ulyanov tweeted following Friday’s meeting that “the participants agreed on the need to intensify the process.”

“The delegations seem to be ready to stay in Vienna as long as necessary to achieve the goal,” he wrote.

The U.S. pulled out of the landmark 2015 deal in 2018 after thenPresident Donald Trump said the pact needed to be renegotiated. The deal had promised Iran economic incentives in exchange for curbs on its nuclear program, and the Trump administration reimposed heavy sanctions on the Islamic republic.

Iran reacted by steadily increasing its violations of the deal, which is intended to prevent the country from obtaining nuclear weapons. Iran began enriching uranium to a greater purity, stockpiling more than allowed and beginning to use more advanced centrifuges in an attempt to pressure the world powers remaining in the deal — Germany, France, Britain, Russia and China — for economic relief.

President Biden says he wants to rejoin the deal, known as the Joint Comprehensive Plan of Action, or JCPOA, but that Iran needs to return to compliance.

Iran, which insists it does not want to produce a nuclear bomb, has said it is prepared to reverse all of its violations but that Washington must remove all sanctions imposed under Trump.

On the other side is the question of what Iran’s return to compliance would look like. Delegates to the Vienna talks concede, for example, that Iranian nuclear scientists cannot unlearn the knowledge they acquired in the past three years, but it is not clear whether Iran’s new centrifuges would need to be destroyed, mothballed and locked away, or simply taken offline.

Because the U.S. is currently out of the deal, there was no American representation at the talks. Diplomats involved are shuttling between the Iranian side and a delegation from Washington elsewhere in Vienna.