A timeline of Trump's escalating deadlines on Iran and the Strait of Hormuz

"A whole civilization will die tonight, never to be brought back again. I don't want that to happen, but it probably will," Trump wrote in a Truth Social post. "We will find out tonight - one of the most important moments in the long and complex history of the world," he added, referencing his 8 p.m. ET deadline for Iran to agree to a ceasefire and reopen the strait.

Trump's warning sharply raises the stakes in the Strait of Hormuz, a narrow but vital artery for the global energy supply, where disruptions have sent oil and gas prices surging worldwide.

The strait is also a vital artery for refined fuels, including products like jet fuel.

Ali Mousavi, Iran's permanent representative to the International Maritime Organization, responded by saying that the Strait of Hormuz was "open to everyone" except Tehran's enemies. Meanwhile, other Iranian officials warned that attacks on energy infrastructure would amount to an attack on the Iranian people and would be met with retaliation.

Iranian officials publicly denied that any talks were taking place.

In a social media post, Trump said the United States would consider a ceasefire only once the strait was "open, free and clear," adding: "Until then, we are blasting Iran into oblivion or, as they say, back to the Stone Ages!!!"

The post followed several conflicting statements in previous days, in which he alternately criticized allies for not acting to reopen the strait and suggested it would reopen on its own.

In a profanity-laced post on Truth Social on Sunday, Trump wrote: "Tuesday will be Power Plant Day, and Bridge Day, all wrapped up in one, in Iran.

"There will be nothing like it!!! Open the F-----' Strait, you crazy b-------, or you'll be living in Hell - JUST WATCH! Praise be to Allah."

"Tuesday, 8:00 P.M. Eastern Time!" he wrote in a second post.