JD Vance and senior Iranian negotiators arrived in Switzerland to formally open a 60-day push to turn last week's interim accord into a broader deal on Iran's nuclear program and the war in Iran.
The talks were jolted almost immediately by fighting in Lebanon and Iran's claim it had closed the Strait of Hormuz, though US Central Command disputed that and Vance said millions of barrels of oil were still moving.
Vance said he would stay only "a day or two," leaving detailed bargaining to envoy Steve Witkoff and Jared Kushner as Iranian delegates including Foreign Minister Abbas Araghchi, parliamentary speaker Mohammad Bagher Qalibaf and oil officials joined the sessions.
The interim agreement lets Iran sell oil freely, unlocks billions of dollars in frozen assets and requires dilution of highly enriched uranium, while allowing commercial ships to use Hormuz for 60 days without charge.
Political and military risks still hang over the process: Trump and Vance face Republican criticism, Trump threatened US tolls on the strait if no deal emerges, and Israel-Hezbollah fighting has already killed 47 people in Lebanon and four Israeli soldiers.