Strait of Hormuz Crisis 2026: US Expands Southern Route, 80 Mines Block Main Channel, and IMO Evacuations Suspended

~80 mines remain in the main shipping lanes

The standard pre-war commercial channel — known as the Traffic Separation Scheme (TSS) — remains closed due to mines. On June 26, the International Maritime Organization (IMO) formally estimated that approximately 80 mines remain in the historic shipping lanes .

According to Chatham House, the mines are primarily Iranian Maham 3 and Maham 7 high-explosive blast mines, which are designed to resist detection by deviating sonar waves used by minesweepers . Intertanko, the independent tanker-owner trade association, has stated that normal shipping cannot resume until these mines are cleared . Phil Belcher, marine director at Intertanko, told the Guardian: "The main route … through the middle of the Strait of Hormuz, that's closed, that's dangerous" .

Takaya Soga, chief executive of Japan's NYK Line, which operates a fleet of more than 900 vessels, warned that shipping through the strait will operate at less than half of prewar levels for months even if the US-Iran peace deal holds, because the available routes are "extremely limited — they're very narrow corridors" .

IMO evacuation program suspended after projectile strike

The IMO, working with Oman, launched a "phased evacuation" plan on June 23 to extract stranded vessels and crews from the Persian Gulf . However, on June 25, the UK Maritime Trade Operations (UKMTO) reported that a cargo vessel had been struck by "an unknown projectile" approximately 7.5 nautical miles southeast of the Omani port of Dahit .

IMO Secretary-General Arsenio Dominguez confirmed the suspension, stating: "I have been informed of an attack today in the Gulf of Oman on a vessel which passed through the Strait of Hormuz. This vessel did not transit under IMO's evacuation framework … Therefore, to ensure a coordinated approach to safety, the evacuation will be paused until further clarity is obtained" .

A US official told CNBC that Iran was behind the attack . A separate Iranian government authority, the Persian Gulf Strait Authority, said on social media after the strike that any ship seeking "safe passage" must coordinate with Iranian authorities and use approved routes .

11,000+ seafarers remain stranded

Before the suspension, the IMO reported that it had successfully evacuated approximately 2,500 seafarers from the Persian Gulf — 115 ships carrying roughly 2,500 crew members left during the first three-and-a-half days of the operation .

Multiple authoritative sources report that the plan was intended to cover more than 11,000 stranded sailors. Al Jazeera specifically reports "more than 11,000 sailors stranded in the Strait of Hormuz" remain in need of evacuation . As of late June 2026, no active evacuation plan is in place for these remaining seafarers.

What this means for global trade and energy markets

The Strait of Hormuz is a vital maritime chokepoint. Before the conflict, its two unidirectional sea lanes facilitated the transit of around 20 million barrels of oil per day — roughly 20% of global seaborne oil trade . The combination of mine contamination, two competing and uncoordinated routing regimes (an Iranian-controlled northern corridor and a US-Omani southern corridor), and the suspension of the IMO evacuation means the strait is far from returning to normal commercial operations. CNBC reports that shipowners are left navigating two competing authorities with no agreed rules .