The statement directly contradicted his own son-in-law and special envoy Jared Kushner, who had said just a day earlier that negotiations with Iran were continuing and were "probably more robust" than ever.
All this came a day after a temporary ceasefire with Iran had expired, with Trump saying he had no intention of extending it, and sent already-stressed markets deeper into uncertainty. Oil prices climbed, stock markets weakened and borrowing costs for major economies including the United States rose to multi-decade highs.
What is actually happening in the Gulf
Preliminary shipping data showed Hormuz crossings remained in single digits on Monday, a number that tells its own story about the state of the waterway Trump described as functioning normally.
Iran's top negotiator Mohammad Baqer Qalibaf said the strait would remain shut until Washington honoured conditions outlined in the June interim agreement: an end to the US naval blockade of Iranian ports, the lifting of oil sanctions, the release of frozen Iranian assets and a halt to military operations and threats.
The memorandum of understanding signed on June 17 had established a 60-day window for broader negotiations on Iran's nuclear programme and sanctions relief. That window closed on Monday.
The UAE escalation
The UAE reported detecting two Iranian ballistic missiles, the first such reported incident since a May 4 strike on Fujairah port, with its defence ministry assessing they were targeting maritime traffic. Both fell into the sea. Iranian Foreign Ministry spokesperson Esmaeil Baghaei dismissed the UAE's account as "baseless."
The UAE Foreign Ministry announced the suspension of all trade, commercial exchanges and financial transactions with Iran until further notice, citing a threat to regional and international peace and security. This came just weeks after direct cargo shipping between the two countries had cautiously resumed through Dubai's Jebel Ali Port following months of suspension.
The UK Maritime Trade Operations separately reported that a vessel was struck by an unknown projectile in the Strait of Hormuz, damaging its engine room and injuring a crew member. Oman's coast guard assisted those on board.
Iran: Open to talks, not surrender
Despite the hardening positions on both sides, Iranian officials maintained that Tehran had not closed the door on diplomacy. Mohammad Mokhber, an adviser to Iran's supreme leader, said Iran remained willing to engage with Washington but would not treat negotiations as capitulation, according to the semi-official Fars news agency. He said military pressure and sanctions would not weaken Iran's determination and that Tehran would defend its security, dignity and allies without seeking war.
Iranian leaders are simultaneously under domestic pressure. Officials acknowledge that continued economic strain risks deepening public hardship, fuelling unrest and weakening the Islamic Republic's internal legitimacy.
The economic toll
The conflict, now approaching six months, has extracted a significant price from global energy markets. Brent crude surged to as high as $126 a barrel at the peak, roughly 75% above pre-war levels. It settled 20 cents higher on Tuesday at just above $91.
A US administration official warned that Washington still had tools it had not deployed. "There are many levers the president can crank harder in the weeks and months ahead," the official said.
Thousands of people have been killed in the conflict, primarily in Iran and Lebanon. Iranian forces have struck US military bases and infrastructure across Oman, Jordan, Kuwait, Israel, the UAE and Saudi Arabia.
(With inputs from PTI)