Iran Threatens Total Closure of Strait of Hormuz Following Donald Trump's Energy Ultimatum

Iran threatened to completely seal the Strait of Hormuz after US President Donald Trump issued a 48-hour ultimatum demanding Iran fully open the passage "without threats," warning he would order the destruction of Iranian power plants if the deadline was not met. The Iranian Revolutionary Guards announced via state broadcaster Irib that the strait would be completely blocked in the event of any US strike on Iranian energy facilities, and would remain closed until any destroyed power plants were rebuilt. Trump posted the ultimatum on his Truth Social platform in the early hours of Sunday, writing that the United States would attack and destroy Iran's power plants, "starting with the largest one!" Web search results confirmed Trump used the word "obliterate" in describing the threatened strikes. Shipping through the strait has already largely ground to a halt as a result of the ongoing US-Israel war against Iran, with Iran repeatedly attacking vessels in the region, though some individual ships have continued to pass through.

Iran widens threat to Gulf energy and Israeli infrastructure Iran's response extended well beyond the strait itself, with the Revolutionary Guards announcing they would strike all power plants, energy infrastructure, and information and communication technology assets belonging to Israel if the United States proceeds with attacks on Iranian facilities. The Guards also threatened to target "all comparable companies in the region with US shareholders," broadening the potential scope of retaliatory strikes across the Gulf. Separately, Iran had already warned it would attack all energy infrastructure and desalination plants with connections to the United States throughout the Gulf region. The threat to desalination plants carries particular weight in a region where several countries depend on them for the majority of their fresh water supply. The layered nature of Iran's response — covering the strait, Gulf energy infrastructure, Israeli power grids, and communications networks — signals a deliberate effort to raise the cost of any US military action beyond Iranian borders. The Strait of Hormuz has long been a focal point of tension between Iran and Western powers. Iran has threatened to close the strait during previous periods of military and diplomatic confrontation. The US-Israel military campaign against Iran, which began on February 28, 2026, and was designated Operation Epic Fury, resulted in the death of Supreme Leader Ali Khamenei in the initial strikes. His son Mojtaba Khamenei was appointed Supreme Leader on March 9, 2026, inheriting leadership of a country already under sustained military pressure.

Global markets face "Black Monday" warning as deadline looms Financial analysts warned of severe market consequences if the standoff escalates further, with web search results citing warnings of a potential "Black Monday" on global markets should the strait be fully closed. The Strait of Hormuz is one of the world's most critical chokepoints for oil trade, and even a partial disruption has historically sent energy prices sharply higher. Shipping through the passage has already largely ceased due to the ongoing conflict, meaning a formal closure would formalise and deepen an interruption already affecting global supply chains. Iran's threat to target desalination infrastructure and energy facilities across the Gulf would compound the economic impact far beyond oil markets alone. The 48-hour deadline Trump set on Sunday morning placed the confrontation on a timeline extending into the early hours of Tuesday, leaving little room for diplomatic manoeuvre. No confirmed information was available from the articles regarding any third-party mediation efforts or diplomatic back-channel activity ahead of the deadline.

War's toll on regional shipping already severe before ultimatum Even before Trump's ultimatum, the Iran war had already inflicted significant damage on maritime traffic through the Strait of Hormuz, with the N-tv report noting that only a few ships were passing through the passage and that navigating it had become "very dangerous." Iran had repeatedly attacked vessels in the region since the start of the US-Israel campaign, though some ships managed to transit the strait individually. The Revolutionary Guards' announcement that the strait would remain closed until destroyed power plants are "rebuilt" suggests Iran is prepared for a prolonged standoff rather than a short-term tactical response. That condition — tying the reopening of a global shipping lane to post-war reconstruction — sets a threshold that would be difficult to meet quickly even under the most favourable circumstances. The Truth Social post in which Trump issued the ultimatum marked one of the most direct public threats by a sitting US president to destroy the energy infrastructure of a sovereign state within a defined time window. The situation remained unresolved as of Sunday afternoon, with both sides publicly committed to their stated positions.