Secretary of State Marco Rubio said in Rome a reply could come later on Saturday, while Donald Trump said at the White House he expected a letter overnight.
The diplomatic push comes after the biggest flare-ups around the Strait of Hormuz since last month's informal truce, and after Trump announced then quickly paused a naval mission to reopen the waterway.
Pakistan has passed Iran a brief US memorandum as a basis for a firmer ceasefire and talks, but Foreign Minister Abbas Araghchi accused Washington of repeated breaches and reckless military action.
As a new US-Iran deal is drafted, what does Washington expect from President Trump's upcoming summit with key Iranian ally China?
With Iran's military reportedly degraded, what leverage does Tehran truly hold in ceasefire talks for the vital Strait of Hormuz?
Is the hantavirus response a critical test of America's pandemic readiness after recent deep cuts to public health agencies?
The May 2026 US-Iran Ceasefire: Strait of Hormuz Instability, Economic Strain, and Diplomatic Deadlock
Overview
As of May 2026, the ceasefire that began in early April remains extremely fragile, with ongoing skirmishes threatening to break the peace. The Trump administration is waiting for Iran’s response to new proposals, while Iran has criticized recent clashes as pressure tactics. Tensions are especially high around the Strait of Hormuz, a key global energy route, where battles continue and the risk of escalation is significant. This unstable situation not only endangers the ceasefire but also puts global economic stability at risk, as disruptions in the Strait impact energy markets and international shipping.