The first high-level US-Iran talks in Switzerland ended with cautious optimism, but the most difficult file inside the emerging diplomatic framework is no longer only nuclear inspections, sanctions relief or the Strait of Hormuz. It is Lebanon.
After nearly 18 hours of talks at Bürgenstock, mediators Qatar and Pakistan said Washington and Tehran had made “encouraging progress” and agreed on a 60-day roadmap toward a final deal. The sides also established technical working groups and a high-level committee to supervise the next phase. Yet the most immediate and politically sensitive outcome was the agreement to create a Lebanon-focused “de-confliction cell” aimed at halting military operations and preventing the Israel-Hezbollah front from collapsing the wider process.
Lebanon has become the pressure point because it sits at the intersection of all the unresolved contradictions in the US-Iran file. Tehran wants guarantees that the broader understanding will reduce pressure on its regional allies and end Israeli military operations. Washington, meanwhile, needs to show that any deal does not simply reward Iran but produces enforceable regional de-escalation. Israel, which is not a direct party to the US-Iran talks, has made clear that it does not see itself bound by arrangements negotiated over its head.
This makes Lebanon the first real implementation test. If the de-confliction mechanism can reduce violence along the Israel-Lebanon front, the Switzerland track may gain momentum. If Israeli strikes continue, Hezbollah retaliates, or Tehran concludes that Washington cannot deliver on de-escalation, the 60-day roadmap could unravel before technical negotiations produce substance.
The issue has already disrupted diplomacy. Earlier delays and tensions around the talks were linked to fighting in Lebanon, while Iran publicly warned that the United States would be responsible for violations of commitments connected to ending hostilities. The latest round survived those pressures, but only by moving Lebanon to the centre of the diplomatic architecture.
The other files remain critical. Sanctions waivers, frozen Iranian assets, oil exports, IAEA access and safe navigation through Hormuz will shape the final bargain. But Lebanon is different. It is where the diplomatic paper meets armed actors, Israeli calculations and Iranian credibility.
For now, the Switzerland talks have kept the US-Iran channel alive. Whether it can mature into a final deal may depend less on what negotiators write in conference rooms than on whether the guns stay quiet in Lebanon.