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Iran Conflict 2026
21MAY

Maersk and CMA CGM halt Hormuz transits

2 min read
09:55UTC

Six of the world's biggest shipping companies have suspended all Hormuz transits after three tankers were attacked in 72 hours — a faster escalation than the entire 1984–88 Tanker War.

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CMA CGM, Maersk, Nippon Yusen, Mitsui, and Kawasaki Kisen have halted all transits through the strait of Hormuz. They join Hapag-Lloyd, which suspended operations within hours of the IRGC's VHF Channel 16 broadcast declaring the strait closed to shipping . Six of the world's largest shipping companies — controlling roughly half of global container capacity — now refuse to send vessels through the passage that carries approximately 20% of the world's traded oil.

The suspensions followed three direct attacks on commercial tankers near the strait: the MV Skylight struck off Oman with four crew injured, the MKD Vyom hit by a projectile that ignited an engine room fire, and the Sea La Donna, details still pending. Oil tankers had already begun avoiding the strait after the opening strikes . The physical attacks converted commercial caution into a full shutdown. Vessel traffic has fallen 70%, with more than 150 tankers anchored in open Gulf waters.

The last sustained military campaign against commercial shipping in these waters was the 1984–88 Tanker War during the Iran-Iraq conflict, which struck 546 vessels over four years. Three have been hit here in 72 hours. When Houthi attacks disrupted Red Sea shipping in 2024, carriers rerouted around the Cape of Good Hope — costly, but viable. the strait of Hormuz has no such bypass. Saudi Arabia's East-West Pipeline and the UAE's Habshan-Fujairah pipeline provide limited overland alternatives, but their combined capacity covers a fraction of normal seaborne Gulf exports.

Every day of closure tightens supply across refineries in Asia and Europe that depend on Gulf crude. Brent opened Saturday at $82.37 (ID:108), up from the pre-strike price of $73 . Goldman Sachs projected a peak of $110 per barrel; JP Morgan forecast $120–130 if the conflict is prolonged and raised its US recession probability to 35% (ID:111). With commercial vessels now under direct fire rather than merely pausing, the prolonged-conflict scenario is the one unfolding.

Deep Analysis

In plain English

The companies did not need to be ordered to stop — insurance requirements and duty-of-care obligations to crews left them little practical choice once vessels began being struck. This is a commercial mechanism, not a political one: governments cannot simply instruct carriers to resume without resolving the underlying threat.

Deep Analysis
Synthesis

Iran has achieved the strategic effect of a blockade without physically closing the strait — the carrier suspensions did that. The burden now falls on governments: naval escorts (escalatory), ceasefire (stalled), or absorbing prolonged supply disruption. Gulf oil-producing states face a simultaneous revenue crisis, giving them independent incentive to pressure both parties towards resolution — an actor not yet prominent in diplomatic reporting.

Root Causes

Suspensions are driven by war-risk insurance requirements — which may refuse cover above a defined threat threshold — combined with duty-of-care obligations to crews. Hapag-Lloyd's early suspension likely acted as a coordination signal: once one major carrier exits, competitors can justify the same decision to shareholders and insurers more easily, producing collective action faster than individual commercial logic would suggest.

Escalation

Naval convoy deployment would make the strait operationally a military corridor — the dynamic the Tanker War produced, culminating in the re-flagging of Kuwaiti tankers under the US flag in 1987, a politically costly commitment requiring sustained naval presence. The current US posture is offensive, not convoy protection, making that transition both harder to execute and more escalatory to announce.

What could happen next?
2 consequence2 risk1 precedent
  • Consequence

    With the world's largest carriers suspended, the effective closure of Hormuz to commercial traffic is already achieved through voluntary withdrawal, making the strategic impact of a formal Iranian blockade declaration largely redundant.

    Immediate · Assessed
  • Risk

    Pressure will mount on the US and allied navies to provide armed escorts for commercial vessels attempting Hormuz transits, risking direct military confrontation with Iranian naval or IRGC maritime forces in the strait.

    Short term · Suggested
  • Consequence

    Emergency surcharges and freight rate spikes will flow through global supply chains within weeks, raising the delivered cost of goods across all economies that import via Hormuz.

    Short term · Assessed
  • Precedent

    The collective voluntary withdrawal of commercial carriers from a major international strait under military threat — without governmental compulsion — establishes that economic coercion through targeted anti-shipping operations is an effective strategy with disproportionate effect.

    Long term · Assessed
  • Risk

    Gulf oil-producing states face an acute revenue crisis if they cannot export their primary commodity, creating incentives for them to exert independent pressure on the US towards a ceasefire or to offer financial inducements to commercial operators to resume transits under risk.

    Short term · Suggested
Sources:gCaptain
Mentions:VLCC →Mitsui O.S.K. Lines →National Security Council (Iran) →Goldman Sachs →United Arab Emirates (UAE) →Islamic Revolutionary Guard Corps (IRGC) →CMA CGM →Iran →Strait of Hormuz →Brent Crude →Saudi Arabia →Oman →Iran-Iraq War →JPMorgan Chase →
First Reported In

Update #7 · Hezbollah enters; tankers burn in Hormuz

gCaptain· 2 Mar 2026
Read original →
Causes and effects
This Event
Maersk and CMA CGM halt Hormuz transits
The suspension by CMA CGM, Maersk, Nippon Yusen, Mitsui, Kawasaki Kisen, and Hapag-Lloyd means roughly half of global container shipping capacity now refuses to transit the waterway carrying 20% of the world's traded oil. Unlike the Red Sea, where Cape of Good Hope rerouting was possible during Houthi disruptions, no viable maritime bypass exists for Gulf hydrocarbon exports.
Led to
Three P&I clubs pull Gulf war risk cover
Major shipping lines halting Hormuz transits signalled risk level that triggered P&I insurance cancellation
Occurred 3 Mar 2026
Read story →
Different Perspectives
Turkey (Shakarab consideration)
Turkey (Shakarab consideration)
Ankara serves as one of two Western-adjacent Iran back-channels while Turkish national Gholamreza Khani Shakarab faces imminent execution on espionage charges in Iran. President Erdogan cannot deflect the domestic political crisis that a Turkish execution would trigger, which would force suspension of the mediating role.
Germany (Bundestag gap)
Germany (Bundestag gap)
Belgium, Germany, Australia, and France committed Hormuz coalition hardware on 18 May. Germany's Bundestag authorisation for the coalition deployment remains pending, creating a constitutional gap between the commitment announced and the parliamentary mandate required to operationalise it.
IEA and oil market analysts
IEA and oil market analysts
The IEA's $106 May Brent projection met the market in one session on 20 May as Brent fell 5.16% on diplomatic optimism. Goldman Sachs and Morgan Stanley's two-layer premium framework holds: the kinetic component compressed; the structural insurance component tied to Lloyd's ROE remains unresolved.
Hengaw
Hengaw
Documented the dual Kurdish execution at Naqadeh on 21 May, the two Iraqi-national espionage executions on 20 May, and Gholamreza Khani Shakarab's imminent execution risk. The 24-hour cluster covers two executions at one facility, the first foreign-national espionage executions, and a Turkish national whose death would suspend Ankara's mediation.
Lloyd's of London
Lloyd's of London
Hull rates stand at 110-125% of vessel value on the secondary market; the Joint War Committee has conditioned cover reopening on written ROE from the coalition or PGSA. The Majlis rial bill makes any compliant ROE structurally impossible to draft while the PGSA's yuan portal remains its operational mechanism.
United Kingdom and France (Northwood coalition)
United Kingdom and France (Northwood coalition)
The 26-nation coalition paper requires Lloyd's to see written rules of engagement before Hormuz war-risk cover reopens. The Majlis rial bill adds a second governance incompatibility on top of the unpublished PGSA fee schedule; coalition ROE cannot mention rial without conceding Iranian sovereignty over the strait.