U.S.-Iran talks begin in Switzerland as Lebanon fighting threatens fragile deal

Delegations from the United States and Iran arrived in Switzerland over the weekend to begin sixty days of technical negotiations on a nuclear agreement and broader regional peace. Vice President JD Vance joined special envoys Steve Witkoff and Jared Kushner at the Bürgenstock Resort overlooking Lake Lucerne, where mediators from Pakistan and Qatar were also present. The talks represented the next phase of a memorandum of understanding signed earlier in the week by President Trump and Iranian President Masoud Pezeshkian, aimed at ending a war that had consumed the region since late February. Yet the negotiations opened under severe strain. Within hours of the delegations assembling, Iran announced it was closing the Strait of Hormuz again—a vital shipping lane through which roughly a fifth of the world's oil passes—accusing the United States and Israel of violating the first clause of their agreement by maintaining military forces in southern Lebanon.

The closure threat exposed the fragility of the deal before serious talks could begin. Iran's military command said the action was a response to what it called bad faith by the United States and Israel's refusal to withdraw from Lebanese territory. The Islamic Revolutionary Guard Corps warned commercial vessels not to approach the strait, saying their security could be at risk if they did. The United States Central Command immediately countered that the strait remained open and that fifty-five commercial vessels had transited it on Saturday alone, moving more than seventeen million barrels of oil to global markets. American forces, CENTCOM said, would remain present and vigilant to ensure all aspects of the agreement were upheld.

The dispute over Lebanon was not abstract. On Friday, the deadliest day of fighting in weeks, Israeli airstrikes killed at least forty-seven people across southern Lebanon, including women and children. Hours after three diplomats told CBS News that Israel and Hezbollah had reached a ceasefire agreement, Israeli strikes resumed overnight Saturday, killing more than a dozen additional people. A Lebanese soldier was killed in one strike on the Kfar Rumman–Nabatieh road, prompting the Lebanese army to accuse Israel of deliberately trying to sabotage any path to peace. The ceasefire, which was supposed to begin Friday morning, had effectively collapsed within hours. Israel said Hezbollah had fired more than fifty projectiles at its forces in southern Lebanon, prompting the military response. Hezbollah countered that any Israeli presence in Lebanese territory constituted a violation of the memorandum of understanding and said it would continue to defend Lebanese land. Neither group had been party to the negotiations that produced the agreement they were now accused of breaking.

Prime Minister Benjamin Netanyahu made clear that Israeli forces would not leave the security zone they had established in southern Lebanon, regardless of what the memorandum stipulated. "Israel will remain in the security zone in southern Lebanon as long as necessary to protect the northern communities," he said. He also vowed that Israel would exact a heavy price from Hezbollah for the deaths of four Israeli soldiers killed in the fighting. The Israeli ambassador to the United States, Yechiel Leiter, said Israel had halted offensive operations at 11:30 a.m. local time on Saturday but reiterated that Hezbollah must be destroyed for Lebanon to prosper. Hezbollah, for its part, said it would continue attacking Israeli troops as long as they occupied Lebanese soil.

The fighting in Lebanon threatened to unravel the entire agreement. The memorandum of understanding explicitly called for an immediate halt to military operations on all fronts, including Lebanon, and for respect for Lebanese territorial integrity and sovereignty. Yet the two parties most directly involved in the Lebanon conflict—Israel and Hezbollah—had not been part of the negotiations. Iran, which backs Hezbollah, had insisted that fighting stop in Lebanon as a condition of any broader ceasefire with the United States. Now, with violence escalating rather than subsiding, Iran was signaling that it considered the agreement already breached.

An emergency session on the Israel-Hezbollah conflict was added to the first day of talks in Switzerland, marking a significant shift in American strategy. For the first time, the United States was allowing Iran to formally introduce the Lebanon fighting into the negotiations. Qatari and Pakistani mediators scrambled to manage the crisis. Secretary of State Marco Rubio said that bilateral talks between Israeli and Lebanese representatives, scheduled for Washington the following week, would still proceed as planned. He underscored that those negotiations represented the only viable path to reconstruction and lasting peace. Yet the violence of the preceding days suggested that path was narrowing by the hour.

President Trump, meanwhile, spent Saturday morning at Camp David posting about the success of his war against Iran. He dismissed criticism from Democrats that Iran was in a stronger position than three months earlier, insisting the country had been defeated militarily. He also threatened to impose tolls on ships passing through the Strait of Hormuz if a final deal was not reached within sixty days, saying the money would be for "services rendered as the Guardian Angel to the countries of the Middle East." The announcement underscored that the agreement called for toll-free passage during the negotiation period. Iran's Supreme National Security Council, for its part, said it had signed the memorandum with complete distrust of the United States and warned that any deviation or violation would bring a reciprocal response. The stage was set for two months of tense, high-stakes negotiations in which every military move in Lebanon, every ship that transited the Strait of Hormuz, and every statement from either side could tip the balance between fragile peace and renewed conflict.