Negotiators settled on 'key parameters' for a future deal now set to be finalized in late June.
The United States, Iran and five other nations have reached a framework agreement for a final nuclear deal this summer.
"We have reached solutions on key parameters on a joint comprehensive plan of action," said European Union foreign policy chief Federica Mogherini during a joint statement in Switzerland Thursday afternoon. Negotiators will now begin drafting the deal, which would curb Iran's nuclear program in exchange for sanctions relief, before the official deadline at the end of June.
The Associated Press reported Thursday morning as "the outlines of an understanding that would open the path to a final phase" of talks over curbing Iran's nuclear program. What they hadn't agreed on, according to AP, was how much of the preliminary framework to make public. But officials offered some specific details during their announcement this afternoon.
All sides have agreed that Iran's enrichment capacity and stockpile "will be limited for specific durations," Mogherini said. The country's uranium enrichment site in Fordo—a source of contention during the talks—will be converted to a nuclear physics and technology center." In accordance with the agreement, the facility can keep its centrifuges, but not for enrichment purposes. The site was a sticking point during the talks as negotiators sought to limit Iran's uranium enrichment levels.
When a final deal is reached, "nuclear-related economic and financial" sanctions imposed by the European Union will be lifted immediately, and the U.S. will grant relief from financial sanctions related to Iran's nuclear program.
The framework agreement comes after marathon negotiations in Switzerland, which blew past a self-imposed deadline on Tuesday. A joint announcement by officials of the European Union and Iran is expected later this afternoon in the city of Lausanne. President Obama, who is scheduled to travel to Louisville this afternoon, remains at the White House.
Negotiators sounded hopeful ahead of the announcement. Javad Zarif, Iran's foreign minister, tweeted an optimistic message Thursday afternoon: "Found solutions. Ready to start drafting immediately."
Iranian President Hassan Rouhani tweeted: "Solutions on key parameters of Iran #nuclear case reached. Drafting to start immediately, to finish by June 30th. #IranTalks."
The negotiations oscillated between productive and faltering this week. Foreign ministers of three of the six world powers left late Tuesday night. One returned less than 24 hours later. Kerry said Wednesday that he would be extending his stay.
Negotiations have revolved around Iran's nuclear research and development capabilities, and the time and scope of sanctions removal should it agree to a deal. Iran has sought to relief from sanctions imposed by the U.S. and other nations that have crippled its economy.
The White House said Wednesday that Iran talks "continue to be productive and progress is being made," a day after the original framework agreement deadline. Press Secretary Josh Earnest said that gaps "still remain in terms of trying to reach an agreement."
While the deadline for a concrete deal isn't until the end of June, this week's milestone was being closely watched in Washington. Congressional leadership had signaled it would move on legislation to impose additional sanctions against Iran "very quickly" if talks fell apart. The Obama administration has said repeatedly that the U.S. no deal is better than a bad deal.
"If we are not able to reach a political agreement, we are not going to wait all the way to June 30 to walk away," Earnest said on Tuesday.
This is a developing story and will be updated.
NEXT STORY: Is Iran a Totalitarian State?