Trump Issues 48-Hour Ultimatum to Iran as Strait of Hormuz Traffic Grinds to a Halt

The world’s most important oil chokepoint is at a standstill. Hundreds of tankers sit at anchor in and around the Strait of Hormuz, their crews waiting for orders that may not come. On land, fuel traders watch price charts lurch higher. And in Washington, a 48-hour clock is ticking.

Late Saturday, President Donald Trump issued an ultimatum to Iran: fully reopen the strait to shipping within two days or face U.S. airstrikes on its power plants.

“If Iran does not FULLY OPEN, WITHOUT THREAT, the Strait of Hormuz within 48 hours,” Trump wrote in a post on his social media platform, “the United States will hit and obliterate their various POWER PLANTS, starting with the biggest one first.”

Tehran, already at war with the United States and Israel, has responded with its own threat. Iranian officials vowed to “completely close” the narrow waterway and to destroy energy infrastructure across the Middle East if their power grid is hit.

The exchange, three weeks into a conflict that has killed Iran’s supreme leader and his de facto successor and triggered the sharpest oil price shock in decades, is transforming a regional war into a global test of energy security and the laws of war.

A chokepoint with global consequences

The Strait of Hormuz, a 21-mile-wide passage between Iran and Oman at its narrowest point, is the main route to sea for crude oil and liquefied natural gas exports from Saudi Arabia, Iraq, the United Arab Emirates, Kuwait, Qatar and Iran. Energy analysts estimate that around a fifth of the world’s oil trade normally passes through the channel.

Since early March, that traffic has all but stopped.

Within days of the United States and Israel launching coordinated strikes on Feb. 28 against Iranian command centers, nuclear facilities and senior figures—including Supreme Leader Ali Khamenei—Iran’s Revolutionary Guard Corps declared Hormuz unsafe. The Guard warned that any vessel attempting to transit could be targeted.

Several commercial tankers were damaged or narrowly missed by missiles and drones in the first week of March, including one vessel struck near the Omani port of Khasab and another attacked near the Emirati coast. Maritime insurers reacted by cancelling or sharply restricting war-risk coverage in Iranian waters and much of the surrounding Gulf.

The result has been visible in satellite images and ship-tracking data: long lines of tankers idling in anchorages off Oman and the UAE and a near-collapse of commercial passages through the strait.

Oil, gas and inflation fears surge

As the shipping slowdown accelerated, benchmark Brent crude climbed above $100 a barrel. U.S. benchmark West Texas Intermediate touched intraday highs near $120, and analysts recorded the largest weekly percentage gain in crude futures since modern trading began in the early 1980s.

Global liquefied natural gas markets tightened as Qatar, a key supplier to Europe and Asia, curtailed exports amid drone threats and insurance limits on tankers.

Beyond the Middle East, higher fuel, shipping and fertilizer costs are feeding back into consumer prices. Central bank officials in Europe and the United States have signaled concern that an extended Hormuz disruption could reverse recent progress in bringing inflation under control.

The legal dispute over “transit passage”

Western governments say Iran’s actions violate international law. Under the U.N. Convention on the Law of the Sea, which codifies rules for most states bordering key waterways, coastal nations must allow “transit passage” for ships through international straits in peacetime, even if they control the surrounding territorial sea.

Tehran argues it is responding to aggression. Iranian officials say the country is under sustained attack from the United States and Israel, which have struck targets deep inside Iran, including the Natanz uranium enrichment plant, and killed top leaders. They insist they are mainly targeting hostile military activity and that some tankers continue to move Iranian exports, suggesting a selective rather than absolute closure.

A war reshapes Iran’s leadership

The air and missile campaign has reshaped Iran’s leadership. Khamenei, who had ruled as supreme leader since 1989, was killed in a Feb. 28 strike in Tehran. After an interim ruling council, the Assembly of Experts named his son, Mojtaba Khamenei, as the new supreme leader on March 8 in an emergency process that analysts say reflected strong pressure from the Revolutionary Guard.

Ali Larijani, a former parliament speaker who was serving as secretary of Iran’s Supreme National Security Council and widely viewed as the key coordinator of the war effort, died in a March 17 Israeli strike in the capital. The same attack killed Gholamreza Soleimani, commander of the Basij paramilitary force.

Iran has responded to the assassinations and strikes on military facilities with multiple barrages of ballistic missiles and armed drones. Cities across Israel, including Beit Shemesh and later Dimona and Arad in the south, have been hit, leaving at least nine people dead and hundreds injured, according to Israeli authorities and hospital officials.

On March 21, U.S. forces used deep-penetrating munitions to hit targets at Natanz, the centerpiece of Iran’s enrichment program. The International Atomic Energy Agency later confirmed structural damage but said there was no radiation leak. Hours later, Iran launched missiles toward the town of Dimona, home to Israel’s Shimon Peres Negev Nuclear Research Center, and the nearby city of Arad, injuring dozens to more than 100 people on early counts.

The IAEA has urged “maximum restraint” around nuclear sites, warning that a miscalculation could lead to an accident with cross-border consequences.

A new front: civilian power grids

Trump’s new ultimatum opens a different front: the civilian power grid.

In a statement carried by state media on Sunday, Iran’s government said any strike on its electricity system would cross a red line and trigger a broader response. Parliamentary speaker Mohammad Baqer Qalibaf warned that Iran would target “critical infrastructure of its neighbors, including energy and oil facilities” if its power plants were bombed.

Iran has previously attacked or threatened desalination plants, refineries and petrochemical facilities around the Gulf. In recent weeks, drones and missiles have struck sites linked to the giant South Pars gas field on Iran’s coast and energy assets in nearby Gulf states, causing injuries and temporary shutdowns.

Human rights and legal experts say the latest threats intensify longstanding concerns about the targeting of civilian infrastructure in war.

Under international humanitarian law, combatants must distinguish between military objectives and civilian objects and ensure that any anticipated civilian harm is not excessive compared with the expected military advantage. Power plants and desalination facilities can be considered military assets if they directly support operations, but destroying them often has devastating effects on civilians.

During the 1991 Gulf War, U.S.-led forces destroyed much of Iraq’s power generation capacity. Subsequent reviews by independent organizations found that electricity shortages crippled water treatment and health systems, contributing to disease and hardship for years.

The stakes are particularly acute in the Gulf, where many countries depend on desalination for the bulk of their drinking water and where summer temperatures routinely climb above 110 degrees Fahrenheit. Disabling major plants or grid nodes for an extended period could create humanitarian crises in densely populated coastal cities.

Diplomacy races the deadline

The conflict has already disrupted daily life across the region. Flights into and out of major hubs, including Dubai International Airport, have been cancelled or rerouted due to security concerns. In Iran, air raid sirens, power cuts and fuel shortages have become more frequent in some areas, according to local reports. In Israel, residents in the path of missile barrages have spent nights in shelters.

Trump and his advisers cast the ultimatum as necessary pressure to restore freedom of navigation.

Administration officials say Iran’s actions at Hormuz amount to economic blackmail and that previous, quieter efforts to coax open the strait failed. They argue that threatening strategic but non-nuclear targets, such as power plants, shows U.S. resolve while stopping short of a ground invasion or direct strike on Iran’s top political leadership.

Critics, including some allied governments, warn that tying such a sweeping threat to a public 48-hour deadline risks locking both sides into escalation. If Iran does not comply, they say, Trump may feel compelled to follow through to avoid appearing to back down, while Iran’s leadership, battered but defiant after the loss of Khamenei and Larijani, may feel it cannot yield under threat without endangering its own grip on power.

Any U.S. strike on Iran’s power sector would almost certainly trigger a response against Gulf energy facilities, which are harder to defend than discrete military bases and whose disruption would reverberate through global markets.

For now, the tankers remain at anchor and the warships at sea. Negotiators from European and regional states are quietly working to see whether a face-saving arrangement—perhaps a monitored corridor through Hormuz, or staggered steps to reduce attacks—can defuse the confrontation.

In shipping offices from Dubai to Singapore, route planners are watching for the first sign that any vessel will risk the strait again. In Washington and Tehran, officials are watching the clock.

Whether the ultimatum leads to a narrow compromise, a limited show of force or a sweeping campaign against power and water systems, the next moves will help decide not only the course of the 2026 Iran war, but whether critical civilian infrastructure becomes a more accepted target in conflicts far beyond the Gulf.