Switzerland confirmed the Burgenstock talks were postponed after Vice-President JD Vance dropped his planned trip, with the White House saying logistics were not yet finalised.
The meeting had been set for technical discussions on implementing this week's 14-point US-Iran agreement, including reopening the Strait of Hormuz, lifting sanctions and starting work on a final deal within 60 days.
Lebanon remained the main immediate fault line: overnight Israeli strikes in the southern Nabatieh district killed at least 18 people, while Israel said it hit Hezbollah targets and lost four soldiers.
That violence has clouded the accord because Iran wants Lebanon covered by any ceasefire, Hezbollah rejects the deal's terms, and Trump has insisted a truce should apply "on all fronts."
On June 18, 2026, Iran halted its delegation’s trip to Switzerland, leading to the suspension of the formal signing ceremony and technical negotiations for the US-Iran peace process. This decision was triggered by ongoing Israeli military operations in southern Lebanon, which Iran viewed as a violation of the interim deal that had previously extended a fragile ceasefire by 60 days. The suspension immediately cast doubt on the recently achieved understanding between the US and Iran, highlighting how renewed conflict in Lebanon can quickly undermine diplomatic progress and threaten the stability of broader peace efforts.