U.S. and Iran haven't backed ceasefire idea as Trump's Hormuz Strait deadline nears

US President Donald Trump disembarks from Air Force One upon arrival at Joint Base Andrews in Maryland, March 23, 2026.

Saul Loeb | Afp | Getty Images

President Donald Trump has not backed an idea for a 45-day ceasefire that would take effect before his upcoming deadline for Iran to either reopen the Strait of Hormuz or else face major attacks on its civilian infrastructure, a White House official told CNBC on Monday.

The note from the official, who spoke on condition of anonymity, came hours before Trump is set to lead a press conference at the White House.

Trump, in a profanity-laced social media threat on Sunday, warned the U.S. would begin strikes on Iranian bridges and power plants unless Tehran agreed to “Open the F----- Strait” by Tuesday night.

The 45-day ceasefire proposal, which could lead to an end to the five-week-old war, is being discussed by the U.S., Iran and a group of regional mediators, Axios first reported Sunday evening, citing sources with knowledge of the talks.

But a White House official, speaking on condition of anonymity, told CNBC on Monday morning, “This is one of many ideas, and [Trump] has not signed off on it.”

“Operation Epic Fury continues,” the official said, noting Trump “will speak more at 1pm” ET.

Trump’s belligerent Truth Social threat that Tuesday “will be Power Plant Day, and Bridge Day, all wrapped up in one” showed him tacitly extending a previously imposed 10-day pause on attacks, which was set to expire Monday.

In a separate post Sunday night, Trump said the new deadline is 8 p.m. ET on Tuesday.

This is developing news. Please check back for updates.

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