U.S. President Donald Trump speaks to the media aboard Air Force One on May 15, 2026, as he returns to the United States.

Alex Wong | Getty Images

President Donald Trump threatened Iran on Sunday to “take action” or appear to face new consequences.

“The clock is ticking on Iran and they better move quickly or there will be nothing left of them,” Trump said in a Truth Social post. “TIME IS IMPORTANT!”

Trump did not provide any information about the exact consequences or the measures he expects Iran to take to avoid them.

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The United States and Iran have been at loggerheads in negotiations to end the war since a tenuous ceasefire was reached in early April. The US continues to block Iranian ports, while Iran has blocked the Strait of Hormuz since the start of the conflict.

But the apparent threat is not the first time that Trump has clearly threatened Tehran on social media. Before the April ceasefire, he warned that “an entire civilization will die tonight and never be brought back” unless Iran capitulates to U.S. demands. He previously threatened to attack civilian infrastructure, including power plants and bridges in Iran, which could constitute a war crime.

The closure of the strait, a key oil channel, has had a devastating impact on the economy, it said oil Prices are rising worldwide and gasoline prices are rising in the United States. The national average price of gasoline in the U.S. was $4.51 a gallon on Sunday, according to AAA.

The US is demanding that Iran abandon its nuclear program and reopen the Strait of Hormuz. Iran is demanding reparations for war damage, an end to the blockade and an immediate end to the fighting, including in Lebanon.

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