U.S. Vice President JD Vance and senior Iranian officials arrived in Switzerland on Sunday to formally begin negotiations on Tehran’s nuclear program, seeking to transform a fragile interim agreement signed last week into a comprehensive deal with major implications for global security and energy markets.
The talks, taking place at the Bürgenstock resort near Lucerne, mark the start of a 60-day effort to resolve the technical aspects of the accord reached between Washington and Tehran following the recent conflict involving Iran.
However, the negotiations opened under mounting pressure after Iran took steps that appeared to challenge the agreement. Tehran announced the closure of the Strait of Hormuz and signaled limited expectations for progress in Switzerland, citing continued Israeli military operations in Lebanon despite a ceasefire arrangement.
The interim deal is already facing its first major test following renewed clashes between Israel and the Iran-backed group Hezbollah earlier this week. Although a new ceasefire brokered on Saturday appeared to be holding, tensions remain high.
Before engaging with Iranian negotiators, Vance met with Pakistani Prime Minister Shehbaz Sharif and Pakistan’s army chief, Asim Munir, who has played a key intermediary role between Washington and Tehran throughout the conflict. Qatari mediators also participated in discussions at the Swiss venue.
Meanwhile, Rafael Grossi, head of the International Atomic Energy Agency, held talks with Swiss Foreign Minister Ignazio Cassis on the sidelines of the negotiations.
Iranian officials indicated that their primary focus would be securing implementation of the ceasefire provisions linked to the agreement. Foreign Ministry spokesman Esmail Baghaei accused the United States of being either unwilling or unable to ensure Israeli compliance with the truce.
Tehran insists that any implementation process must begin with an end to ongoing regional hostilities, including fighting between Israel and Hezbollah. Iranian negotiators held separate consultations with Pakistani and Qatari mediators before a planned four-party meeting involving the U.S. delegation.
Iran is approaching the talks cautiously following previous rounds of nuclear diplomacy that were interrupted by major military confrontations. “The implementation of any document is more important than its signing,” Baghaei said.
At the same time, Iranian President Masoud Pezeshkian reaffirmed Tehran’s position on uranium enrichment, stating that Iran would not relinquish what it considers its right to maintain a nuclear program.
“What is certain is that we will never back down from the right to enrich uranium, and the other side is also forced to accept it,” Pezeshkian was quoted as saying by Iranian state media.
Vance’s trip had originally been scheduled for Friday but was postponed after fighting intensified in Lebanon and Iranian officials temporarily withdrew from the planned negotiations.
The U.S. delegation also includes special envoy Steve Witkoff and Jared Kushner, who are expected to lead much of the technical work on the nuclear file.
The agreement has generated significant controversy in Washington. Critics within the Republican Party have compared it to the 2015 nuclear accord negotiated under former President Barack Obama, which was later abandoned by Donald Trump in 2018.
Under the interim framework, Iran would be allowed to resume unrestricted oil exports and potentially regain access to billions of dollars in frozen assets. In return, Tehran would dilute its stockpile of highly enriched uranium, some of which is believed to be stored at facilities targeted in U.S. strikes last year.
The deal also provides for commercial shipping to pass through the Strait of Hormuz without additional charges for 60 days, though it leaves open the possibility of future Iranian fees. Trump, however, warned on Saturday that the United States could impose its own tolls on the waterway if no final agreement is reached within the allotted period.
Global markets are closely watching the outcome of the talks. Oil prices fell sharply after the agreement was announced last week, but investors remain concerned about the stability of the ceasefire and the future of one of the world’s most critical energy transit routes.
Complicating the negotiations further is the fact that neither Israel nor Hezbollah is a signatory to the U.S.-Iran agreement. Israeli Prime Minister Benjamin Netanyahu has vowed to maintain Israeli forces in southern Lebanon until all threats to Israel are eliminated, while Hezbollah has refused to halt its attacks without an Israeli withdrawal.
According to reports, fighting between Israel and Hezbollah in the days following the U.S.-Iran agreement left 47 people dead in Lebanon and four Israeli soldiers killed, underscoring the fragile security environment surrounding the diplomatic effort.
