Tehran reimposed a blockade on the strategic Strait of Hormuz on April 18, 2026, a day after briefly reopening the vital waterway, further escalating tensions that have embroiled the region in wider hostilities. Iran said the closure was in response to what it described as a US naval blockade of Iranian ports and shipping, which Tehran says violates the truce terms agreed by the warring parties.
US President Donald Trump warned Iran not to “blackmail” Washington with threats to the strait. “We’re talking to them. They wanted to close up the strait again — you know, as they’ve been doing for years — and they can’t blackmail us,” he said at a White House event.
Iran’s Islamic Revolutionary Guard Corps (IRGC) issued stern warnings, saying any ship approaching the strait would be “targeted” and ordering that no vessel should leave anchorage in the Persian Gulf and the Sea of Oman. The IRGC also cautioned the US Navy that it would suffer a “hard blow” if it attacked Iranian vessels. Iran’s newly appointed supreme leader, Mojtaba Khamenei, declared the navy ready to “make the enemies taste the bitterness of new defeats.”
Multiple maritime incidents were reported near the strait on April 18. The UK Maritime Trade Operations (UKMTO) logged a second attack when an unknown projectile struck a container vessel about 25 nautical miles northeast of Oman, damaging containers. Earlier, two IRGC gunboats reportedly opened fire on a tanker transiting the strait. A third incident involved a cruise ship master sighting a close-range splash near his vessel. Separately, India summoned Iran’s ambassador to New Delhi to convey deep concern after two Indian-flagged ships came under fire in the area; New Delhi stressed the importance of safe passage for merchant shipping to and from India.
The conflict’s wider toll was highlighted by Iranian state figures and independent groups. Iran’s state-run Foundation of Martyrs and Veterans Affairs put deaths since the conflict began on February 28 at 3,468. Human Rights and local medical sources have published similar—and in some cases higher—tallies, with some reports from rights groups citing more than 3,600 killed, including many civilians and children.
On the diplomatic front, Tehran said it was reviewing “new proposals” from the United States, but Iran’s Supreme National Security Council stressed Iran would defend its interests and make no compromises it judged unacceptable. Deputy Foreign Minister Saeed Khatibzadeh said Iran was not yet ready for a new round of face-to-face talks, accusing Washington of maintaining “maximalist” demands. He also rejected claims that Iran would ship enriched uranium to the US, calling such an idea a “non-starter.” No date has been set for the next round of Pakistan-brokered US‑Iran talks; Iranian officials said a framework agreement must be finalized before in-person meetings proceed.
Violence linked to the wider conflict also struck Lebanon. UN peacekeepers (UNIFIL) in southern Lebanon came under small-arms fire during an explosives-clearing patrol in the village of Ghandouriyeh, in an incident UNIFIL attributed to “non-state actors” (allegedly Hezbollah). One peacekeeper was killed and three were injured. Separately, an attack on a UNIFIL unit left a French peacekeeper dead and several others wounded; French President Emmanuel Macron and Germany condemned the attack and demanded accountability. Lebanon’s prime minister called for an immediate investigation.
In southern Lebanon, Israel said it had killed militants after they crossed a de-facto “yellow line” referenced for the first time since a recent ceasefire, describing the crossings as violations that posed immediate threats to Israeli forces.
The situation remains fluid: maritime incidents continue, diplomatic contacts are tentative, and both Tehran and Washington signal limited willingness to back down. International concern is rising over the risks to global energy shipments through the Strait of Hormuz and the potential for broader regional escalation.