Ship Calm & Carry green – Attack and Closure of the Strait of Hormuz

Ship Calm & Carry green – Attack and Closure of the Strait of Hormuz

Background

On the night of 28 February 2026, an attack on Iranian soil marked the beginning of an open multilateral conflict which resulted in Iran closing the Strait of Hormuz.

The geographical particularity of this strait is decisive: unlike other strategic passages such as the Suez Canal or the Strait of Malacca, the Strait of Hormuz offers no possibility of maritime bypass.

Measuring 40 miles (212 km) in length and 22.5 miles (55 km) in width, the strait at the entrance to the Persian Gulf is of undeniable strategic importance.

Since the agreement of 1st January 1975, Oman and Iran have jointly ensured the supervision of free transit. In reality, all transit takes place in the Omani part of the Strait.

This is why Iran claims, rightly or wrongly, that this part of the Strait has been mined, in order to divert vessels towards Iranian waters and impose a passage fee on them.

The safest shipping paths would then be those announced by Tehran, passing through Iranian territorial waters around Larak Island.

Ceasefire and consequences

With the ceasefire of the 8th of April 2026, the conflict between the United States, Israel and Iran appeared to have resulted in a status quo. However, this ceasefire did not allow navigation through the Strait of Hormuz to be permanently restored.

If the waters of the Strait have actually been mined, no vessel would reasonably take the risk of crossing them and endangering persons and property. The only remaining solution would be to use a safe passage close to the Iranian coast, entirely controlled by Iran.

The initial two-week ceasefire plan included authorisation for Iran and Oman to levy fees on vessels transiting through the Strait of Hormuz, including through cryptocurrencies, with exemptions for certain allied countries to Iran. Though, it wasn’t immediately implemented.

On 18 May 2026, Iran announced the official creation of a a governmental organizationnamed the “Persian Gulf Strait Authority”, responsible for approving passage through the Strait of Hormuz. As this authority is exclusively Iranian, the United States reportedly expressed their wish for joint management and fees collecting, with no success.

As a result of the ceasefire, the UN called on Iran to stop obstructing navigation in the Strait of Hormuz. This appeal, however, did not find an echo in the Iranian camp.

Final escalation and economic issues

On 8 July 2026, the United States denounced the ceasefire agreement between Tehran and Washington. The Strait was never genuinely reopened to free and unobstructed passage.

At best, a maximum of 30 ships could transit per day during the ceasefire period, compared to more than 120 per day in peacetime.

Navigation remained extremely dangerous, as three transiting vessels were struck within a 24-hour period on 7 July 2026 by Iranian strikes.

The values at risk are estimated at between USD 120 billion and USD 160 billion for vessels transiting through the Persian Gulf alone, excluding the value of the goods transported (goods valued several million euros per ship).

Legal framework introduction

While maritime law has always considered that the risks inherent in a maritime venture should be distributed among its participants, it is nevertheless necessary to consider:

  • the legal characterisation of a passage fee imposed for crossing a strait
  • the legal characterisation of the payment of such a fee by shipowners
  • its possible coverage by one or more parties involved in the transport operation

This Legal Design addresses cargo vessels only and is mainly based on public international law, European Union law, French transportation and insurance law, as well as, more occasionally, other national laws.

Possible sanctions and limitations of the international tribunal for the law of the sea (ITLOS) 

UNCLOS does not provide for any sanction in the event of a breach of its obligations.

 

It merely provides that, in the event of a dispute, States must attempt to resolve it by any peaceful means. Unfortunately, the peaceful resolution path has long been abandoned by the parties.

The Convention provides a legal possibility for compelling a State: bringing proceedings against the State at fault before the International Tribunal for the Law of the Sea (ITLOS), the International Court of Justice, or an arbitral tribunal.

For a state to be sanctioned, all of the following must apply:

  • The offending state must be a signatory and have ratified UNCLOS
  • It must recognize the jurisdiction of ITLOS, ICJ, or another judicial body
  • It must be brought before a court it acknowledges
  • The claimant state must prove:
    • A breach of international maritime law obligations by the offending state;
    • Actual harm/damage suffered by the claimant.

 

However, from 1996 to 2021, no ITLOS decision sanctioned a violation of international law concerning freedom of navigation through a maritime strait.

ITLOS mainly orders reparation, compensation or provisional measures, but no financial sanctions.

 

Therefore, If Iran were:

  • Brought before ITLOS
  • Accepted its jurisdiction
  • Recognized UNCLOS applicability

ITLOS could only order full reparation for damages caused by Iran’s imposition of a transit tax in the Strait of Hormuz.

We can see the limits of public international law, which can only function thanks to and through the will of sovereign states, to commit themselves to conventions and to agree to submit their actions to supranational judicial bodies.

 

➡️For any questions regarding environmental, energy or transportation law, please contact Fanny Berrezai.