The first round of peace talks between the United States and Iran was temporarily paused on Sunday in Switzerland after disagreements over Lebanon and a brief walkout by the Iranian delegation following comments made by US President Donald Trump. Despite the tensions, Tehran insisted that negotiations had not collapsed and said discussions would continue.
Questions over the future of the talks were also raised by Republican Senator Lindsey Graham, who predicted that the diplomatic effort would ultimately fail. Graham said he believed President Donald Trump could take control of the Strait of Hormuz by force if the negotiations collapsed.
The talks in Switzerland took place under a 14-point Memorandum of Understanding (MOU) signed last week between the US and Iran. The agreement established a 60-day ceasefire period during which both sides are expected to negotiate a broader deal.
Graham said he supports trying a diplomatic approach before considering other options. “I’d rather try diplomacy than take it off the table,” he said.
However, he added that he does not expect the negotiations to produce a lasting breakthrough. “If you don’t have a diplomatic path through the MOU, then you have to go to war or some other form of coercion. Let’s try this. Let’s try a diplomatic solution. I think it’s going to fail.”
Graham says Trump could seize the Strait of Hormuz
The senator also revealed details of a lengthy conversation he recently had with Trump. According to Graham, he spent four-and-a-half hours with the president on Friday and came away believing that Trump is prepared to take dramatic action if the peace process falls apart.
“I spent four-and-a-half hours with President Trump on Friday. Here’s what I think will happen next. If this deal fails, President Trump is going to take the Strait of Hormuz over by force,” Graham said. He went even further, warning that the US would respond aggressively if Iran challenged such a move.
“If Iran contests control of the Strait of Hormuz by the United States, we will obliterate them.”
Graham’s comments came just as the first round of talks in Switzerland appeared to hit turbulence. The Iranian delegation reportedly walked out of the negotiations after President Donald Trump’s latest threats over the Strait of Hormuz and Hezbollah, with Tehran later demanding an apology before any official meetings with the US could continue.
While American officials insisted discussions were still ongoing, several Iranian news outlets claimed that Tehran had paused the talks and once again moved to close the Strait of Hormuz.
Trump’s latest warnings to Tehran
According to Fox News correspondent Trey Yingst, Trump held a heated phone conversation with Iranian President Masoud Pezeshkian after Tehran moved to close the Strait of Hormuz. Yingst reported that Trump warned the Iranian leader after comments about continuing uranium enrichment.
“He better watch his mouth… or we will take over the rest of the country,” Trump reportedly said. The president also allegedly warned Iranian officials involved in the Switzerland talks.
“You close it, and you won’t have a country… You won’t even make it back to your country,” Trump reportedly told them, according to Yingst.
Trump also publicly warned on Sunday that Iran would face severe consequences if it interfered with shipping through the strait. He floated the possibility of imposing fees on vessels passing through the waterway if the United States ends up acting as its “guardian angel.”
The president further vowed to “hit Iran very hard” if Tehran fails to stop Hezbollah or other Iran-backed groups from attacking Israel.
Despite his grim assessment of the Iran talks, Graham predicted that Trump would succeed in bringing Saudi Arabia into the Abraham Accords before the end of 2026 and help normalise relations between Riyadh and Israel.
Trump’s comments trigger walkout
The atmosphere became more tense after Trump warned Iran to rein in its allies in Lebanon or face serious consequences. Iranian media reported that the delegation briefly walked out of the talks in protest.
According to Tasnim News Agency, the Iranian team objected to Trump’s remarks and temporarily left the venue during the negotiations.
Following the incident, Qalibaf warned Washington to be careful with its public statements and said Iran’s armed forces were ready to respond if necessary.
Despite the disagreement, Vance sought to play down the incident and stressed that progress was still being made. “These things are always a little bit messy,” he told reporters.
Tehran later informed organisers that its delegation would not participate in any joint media appearances connected to the talks.