Iran-US diplomacy is facing fresh uncertainty after planned talks in Switzerland were postponed and both delegations delayed travel. Questions are mounting over whether the fragile memorandum can survive rising tensions linked to Lebanon, sanctions, nuclear negotiations and the Strait of Hormuz. Vice President JD Vance's trip was put on hold, while reports suggested Iran also delayed participation amid concerns over Israeli military operations. Although both sides insist the agreement remains alive, the suspension of talks has fueled speculation about the future of the 60-day negotiation process and whether the historic deal can withstand growing regional pressures.