U.S. and Iran engage in crucial talks in Switzerland amid escalating tensions and Iran's closure of the Strait of Hormuz.

Iran re-shut the Strait of Hormuz Friday, citing US regional military presence and Israel's actions in Lebanon, despite a recent memorandum signed by both nations' leaders.

Iran to Send Delegation to Switzerland to Follow Up on U.S.-Iran Agreement, State Media Reports. Vance Says U.S. Officials on Ground for Iran Talks; No Evidence Tehran Is Closing…