OBBUERGEN, Switzerland — High-level U.S.-Iran talks on their interim deal to end the war had a tense start Sunday in Switzerland as Tehran took offense at comments by President Donald Trump, who threatened to attack and told Iran’s president to watch what he says.
The comments from afar — on social media and to news outlets — complicated efforts by Vice President JD Vance and mediators Pakistan and Qatar to keep Iran engaged in discussions meant to address thorny issues like Tehran’s nuclear program, the Strait of Hormuz and the unfreezing of billions of dollars in Iranian assets.
Before anything, however, Iran wants to discuss Lebanon, where Israel’s military has been fighting the Iranian-backed Hezbollah militant group, since the deal halts conflict on all fronts.
“Iran must immediately stop their highly paid PROXIES in Lebanon from causing trouble,” Trump said on social media. “If they don’t, we’ll hit Iran very hard again, just like we did last week, only harder!!!”
“They would do better to be careful about their statements,” Iran’s lead negotiator, Mohammad Bagher Qalibaf, said on X after Trump’s comments. “Our armed forces are prepared to respond to them in a different manner. They may keep talking, it is we who act.”
Iranian state media said talks had entered a “difficult phase” and recessed after the “publication of an insulting message by the U.S. President.” The Iranian delegation then met with Qatari mediators and left the negotiating site, state media said.
Vance and U.S. negotiators including Steve Witkoff and Jared Kushner, Trump’s son-in-law, had met with Qalibaf and Foreign Minister Abbas Araghchi for what Iranian state media said was about 80 minutes.
An official with knowledge of the talks later told the AP the Iranian delegation remained engaged in the talks and has not indicated to mediators any intention to leave. The official requested anonymity due to the sensitivity of the talks.
Iran first wants to focus on Israeli strikes in Lebanon
The on-again, off-again conflict in Lebanon between Israel and Iranian-backed Hezbollah militants continues to threaten to derail the effort for the U.S. to win concessions from Tehran on its nuclear program and keep the strait open.
“The question before us now is how much more can we accomplish together? Can we turn over a new leaf?” Vance said as the talks, dubbed the “Lake Lucerne Summit,” got underway.
“Can we change relations in the Middle East permanently, or do we go back to doing things the old way, which is not our preference, but is certainly very much something that can happen.”
Brennan: This will allow Iran to sell its oil based on pre-war production levels, between 150 and $200 million every day, up to $6 billion per month. What do you think they will spend that money on?
Waltz: If it's not going to the places that were agreed upon, we can absolutely… pic.twitter.com/8MJxT8ch03
— Acyn (@Acyn) June 21, 2026
Iranian Foreign Ministry spokesman Esmail Baghaei told the country’s state news agency that their team’s negotiations looked to focus on the war between Israel and Hezbollah in Lebanon.
The interim agreement was signed last week, and top American and Iranian negotiators are in a 60-day sprint to reach an agreement on the technical details that hold massive implications for the world economy and global security.
Only days after signing the agreement, it was stress-tested after fighting escalated in Lebanon between Israel and the Iranian-backed militant group Hezbollah — and by the subsequent announcement by Iran’s military that it had again closed the vital waterway. Still, a renewed ceasefire in Lebanon, brokered on Saturday, appeared to be holding.
The agreement signed by Trump and Iranian President Pezeshkian immediately allows Tehran to sell its oil freely and paves the way for Iran to tap into billions of dollars in assets that are currently frozen. It also calls for Iran to dilute its stockpile of highly enriched uranium, believed to be buried under nuclear sites that were targeted in U.S. strikes last summer.
Pezeshkian, however, has insisted on Iran maintaining its right to enrich uranium.
He repeated that stance on Sunday. “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 said, according to Iran’s state media.
Trump, in a telephone interview Sunday with Fox News, warned that the Iranian president should watch what he says and threatened to take over the rest of the country, in comments relayed by a Fox correspondent.
A delayed meeting is now back on
Vance had originally been slated to be on the ground at the Bürgenstock resort near Lucerne on Friday, but his departure from the United States was delayed after fighting escalated in Lebanon and Iranian officials canceled plans to attend the talks.
U.S. Central Command disputed Iran’s claim that it had once again shuttered the strait and said U.S. forces continued to monitor the situation to ensure traffic continues to flow through the waterway. Vance has said that millions of barrels of oil have moved through the strait in recent days.
Vance departed the U.S. just after Iranian state TV said Iran’s negotiators had arrived in Switzerland.
The vice president was joined by special envoy Steve Witkoff and Jared Kushner, Trump’s son-in-law, for Sunday’s talks. Witkoff and Kushner were on the ground in Switzerland ahead of Vance to begin sifting through the technical details of the nuclear talks.
Vance and his wife, second lady Usha Vance, arrived at Emmen Air Base outside Lucerne just before 6 a.m. local time, according to his office.
While Vance said he planned to be in Switzerland for just “a day or two,” leaving much of the detailed negotiations to be spearheaded by Witkoff and Kushner, his role in the talks has heightened scrutiny of the vice president at a time when he’s actively considering a 2028 presidential campaign.
The deal has stirred much controversy
Trump and Vance have come under searing criticism from parts of their own party for the deal, with Republican hard-liners unfavorably likening it to a nuclear agreement signed by the Obama administration that Trump and the GOP have insisted did nothing to actually terminate Iran’s nuclear program.
The agreement signed by Trump and Iranian President Pezeshkian immediately allows Tehran to sell its oil freely and paves the way for Iran to tap into billions of dollars in assets that are currently frozen. It also calls for Iran to dilute its stockpile of highly enriched uranium, believed to be buried under nuclear sites that were targeted in U.S. strikes last summer.
The agreement says commercial vessels can pass through the Strait of Hormuz for 60 days without a charge, but does not preclude future fees imposed by Iran. Trump made his own threat on Saturday to levy U.S. tolls on the strait if there is no deal with Iran in 60 days, insisting in a social media post that the money would be for “services rendered as the Guardian Angel to the countries of the Middle East.”
The Trump administration has been working to reassure global markets that the Iran war has been merely a blip on oil prices, as Americans complain the conflict resulted in hiking gasoline prices ahead of peak summer travel months. After the White House announced the deal a week ago, oil futures dropped almost 8% — and markets are expected to closely track the progress of talks when they open for trading on Sunday evening.
Further complicating matters, neither Israel nor Hezbollah is a signatory to the deal between the U.S. and Iran, and Israeli Prime Minister Benjamin Netanyahu has vowed to keep his forces in southern Lebanon until any threat to Israel is eliminated. Hezbollah has refused to halt its attacks unless Israel commits to withdrawing from Lebanon.