The United States resumed its naval blockade of all Iranian ports on Tuesday, prompting Iran’s Revolutionary Guard to declare that the Strait of Hormuz would remain closed and to threaten the closure of other energy export routes serving American and allied interests. The US Central Command confirmed that the interdiction of vessels transiting to and from Iranian coastal areas took effect at 4 p.m. Eastern Time, while the IRGC stated that “either the export of oil and gas from the region is available to everyone, or it will not be available to anyone.” The move, which follows a previous two-month blockade between April and June, effectively dismantles the memorandum of understanding signed on 17 June that had codified a ceasefire reached in April, according to Iran’s deputy foreign minister.

The blockade was accompanied by a fourth consecutive night of US strikes on Iranian military infrastructure. CENTCOM said it had completed a seven-hour wave of attacks using fighter jets, drones and naval vessels, targeting missile and drone sites, naval capabilities and coastal defence systems near the Strait of Hormuz and along Iran’s coastline. Iranian state media reported explosions in Bandar Abbas, Qeshm Island and Bushehr. In retaliation, the IRGC launched cruise missiles and drones at what it described as a US logistics centre in Kuwait’s Mina Abdullah area, facilities used by the US Fifth Fleet in Bahrain, and the Azraq airbase in Jordan. Jordan’s military confirmed it had intercepted three ballistic missiles fired from Iran. Kuwait reported fresh drone attacks after an earlier strike injured four soldiers, and the UAE said two of its tankers were hit by Iranian missiles in the strait, killing one Indian crew member.

Shipping data from Kpler showed a brief surge in Iranian-linked traffic through Hormuz on Tuesday, with nine of eleven transiting vessels using the Iranian route, including empty crude tankers inbound and laden tankers carrying crude, refined products and LPG outbound. No tankers from other Gulf producers were observed entering or leaving the strait that day. Analysts at Goldman Sachs noted that the next phase of any recovery in Gulf oil flows is likely to be slower than the initial phase, even if geopolitical tensions ease, pointing to a sharp drop in traffic along Omani and international corridors after recent attacks on commercial vessels. The United Nations has warned of “severe socio-economic and humanitarian consequences” from the paralysis of the strait, which before the conflict handled roughly one-fifth of global oil and liquefied natural gas supplies.

Viewed from Washington, the blockade and expanded targeting of power plants and bridges—threatened by President Trump for the following week unless Iran returns to negotiations—are designed to force Tehran into a new agreement. Trump withdrew an earlier proposal to impose a 20 per cent fee on Hormuz transits, saying he would instead pursue trade and investment pacts with Gulf states. Saudi Arabia, the world’s largest crude exporter, has already diverted most of its shipments to the Red Sea, but the presence of Iran-aligned Houthi forces near the Bab el-Mandeb strait raises the risk of further disruption to global energy supply chains. With the ceasefire memorandum effectively voided and both sides signalling further military action, the dossier remains locked in an escalatory cycle with no immediate diplomatic off-ramp.