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Autonomous Systems: Land & Sea
13JUN

Korean ships sail past the IRGC order

3 min read
11:07UTC

Five more South Korean-operated vessels cleared the Strait of Hormuz on 25 June, 11 of roughly 24 stranded, sailing under a toll-free window and ignoring the IRGC's compulsory Channel 16 mandate declared the same day.

TechnologyDeveloping
Key takeaway

Korean vessels treated the IRGC's Channel 16 order as words, transiting Hormuz without coordinating or being stopped.

Five more South Korean-operated vessels cleared the strait of Hormuz on Thursday 25 June, bringing the total to 11 of roughly 24 stranded since Iran's Islamic Revolutionary Guard Corps (IRGC) closed the waterway on 11 June⁠1. The ships sailed under the toll-free window of the Islamabad memorandum and did not coordinate with the Channel 16 mandate the IRGC had just declared compulsory that morning. South Korea's Ministry of Oceans and Fisheries said its ships were "passing through the strategic waterway and sailing normally"⁠2.

the strait of Hormuz is the narrow gap between Iran and Oman that carries roughly a fifth of global seaborne crude. South Korea is a flag state whose vessels were caught on the wrong side of the closure, and its government is the actor here, not Tehran. Twenty-one Korean sailors were aboard the five ships that left; 13 vessels remain stranded. Seoul's ministry confirming a normal transit is, in practice, a refusal to enforce the corps's order on its own fleet.

This is where the action-versus-words ledger lands on the water. The IRGC issued its mandate; the Korean masters declined to acknowledge it and sailed regardless. The corps had already demanded insurance registration and scheduled tolls from August, yet has interdicted no foreign hull to back any of it. Each Korean departure widens the distance between what Iran says governs the waterway and what actually moves through it.

Deep Analysis

In plain English

When Iran's military declared the strait of Hormuz closed in mid-June, about 24 South Korean cargo ships became stuck inside The Persian Gulf with their crews aboard, unable to leave. On 25 June, five more of those ships managed to sail out through the strait. They used a route announced by international shipping organisation the IMO and Oman, which Iran's military had declared unacceptable that same day. The ships sailed anyway, ignoring Iran's demand to radio the Guards Corps for permission first. By the end of Thursday, 11 of the 24 had made it out. Thirteen remain inside. South Korea's government confirmed the ships were passing through 'normally' but said nothing about the IRGC's Channel 16 instruction.

Deep Analysis
Root Causes

South Korea's vulnerability stems from a structural dependency: it imports roughly 60% of its crude from Gulf producers, and a significant fraction transits Hormuz directly. The 24 stranded vessels reflect the pre-war routing optimisation in which Korean operators ran eastern-destination cargoes through the strait rather than adding 1,200 nautical miles via the Cape of Good Hope bypass.

Seoul's foreign-policy neutrality explains the approach. South Korea maintains full diplomatic relations with both Iran and the United States and has avoided taking a formal side in the Hormuz governance contest. That neutrality is the precondition for the MOU-window transit: Korea can use the Oman-IMO framework precisely because it has not publicly backed any claimant, and it can ignore the IRGC mandate precisely because it has not endorsed it.

What could happen next?
  • Precedent

    Seoul's transit without Channel 16 acknowledgement establishes a de facto governance norm: the Oman-IMO corridor trumps the IRGC mandate in practice, regardless of the legal contest, as long as the corps does not enforce.

  • Risk

    The 13 remaining Korean vessels represent a leverage point: the IRGC could detain one to reassert the Channel 16 authority the Korean transits have implicitly negated, triggering a diplomatic crisis between Seoul and Tehran.

First Reported In

Update #138 · Three flags over Hormuz, none enforced

Korea Times· 25 Jun 2026
Read original →
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Written with AI from Lowdown's published reporting. Not individually reviewed by an editor. Editorial standards.