Encouraging European Military Efforts to Reopen the Strait of Hormuz

Although the new European-led military initiative signals a divergence from the current U.S. approach, Washington could still harness Paris and London’s ability to mobilize international action on the shared goal of preventing Tehran from flexing its leverage over global energy markets.

This week, military planners from over thirty nations met in London for a two-day conference aimed at drafting a detailed plan to reopen the Strait of Hormuz. The meeting came just days after Paris hosted fifty-one countries to showcase diplomatic support for a multinational defensive mission to protect shipping in the crucial waterway once conditions allow.

By insisting on reopening the strait, this new initiative could be perceived as conflicting with the current U.S. strategy of blockading Iranian ports in order to strangle the regime economically. Yet the European effort is broadly consistent with U.S. objectives, especially the goal of preventing Tehran from flexing its newfound leverage over global energy markets. Indeed, the regime sharply criticized the Paris meeting, with senior official Ali Akbar Velayati calling it a “ridiculous show” and quipping, “[I]f England and France are truly concerned about the security of shipping, they should think of a solution for the English Channel and the healing of the old wound in Gibraltar.”

Coalition Building in a New Transatlantic Context

In the past, many European governments—especially close allies like the United Kingdom and Denmark—automatically supported American security efforts, but the Iran war shows that this era is over. The current transatlantic disagreements should not be confused with hostility, however. European leaders are not willing to defy America’s overarching strategy toward the Iran crisis. Rather, they are trying to elaborate what political and military role they want to play—and are capable of playing—in this new context.

The UK and France are leading the way by advancing a multinational mission to reopen the Strait of Hormuz. The stakes are particularly high for London, which has taken harsh U.S. and domestic criticism for the troubles it experienced with rapidly deploying naval assets to the region after Akrotiri Air Base in Cyprus was targeted in early March by Iranian-made drones launched from Lebanon. The next phase of the crisis is a great opportunity to showcase the continent’s ability to formulate a viable military strategy. In fact, many Europeans believe they are doing what the Trump administration is largely unwilling to do: assemble a broad international coalition of willing partners who share an important long-term strategic objective despite their differences.

A Race Against Time

Perhaps the most difficult aspect of planning a European-led mission lies in how to deploy multinational forces swiftly once the British and French prerequisite of a “permissive environment” has been met. This concept remains vaguely defined, particularly regarding the extent of communication required with Iran, so it may not pose as much of an obstacle as some fear. Yet swift implementation may be arduous for countries like Germany, which insists on a robust international legal framework (e.g., a UN Security Council resolution) and domestic parliamentary approval before committing to any operation.

The fact that Paris and London did not convene a military planning conference until two weeks after the current ceasefire was announced raises legitimate doubts about their ability to deploy as quickly as developments demand. Yet the ongoing military tit-for-tat between the United States and Iran—including the regime’s seizure of vessels for the first time during this crisis—gives European officials more time to put together a substantial international effort. (For more on the vessel seizures and other recent incidents in the strait, see the interactive Washington Institute map “Maritime Attacks in the MENA Region.”)

Escorting Ships and Clearing Mines to Lower Oil Prices

The European view is that a multinational force will have a major role to play in restoring prewar Gulf maritime traffic flows regardless of when a permanent ceasefire is reached. Even in the most optimistic scenario—the swift conclusion of a U.S.-Iran deal—returning to normalcy will not happen overnight. Hence, the objective of an escort mission will be to protect merchant vessels in order to accelerate market stabilization and bring oil prices down—a top objective of the Trump administration, which has already renewed its waiver allowing countries to buy sanctioned Russian crude at sea amid severe supply disruptions.

Governments contributing to this military effort will also be able to participate in other operations aimed at ensuring freedom of navigation, including mine clearance efforts. One of the arguments that Iran’s Islamic Revolutionary Guard Corps has used to convince ships to change their routes in the strait is “the likelihood of the presence of various types of anti-ship mines in the main traffic zone.” Given the difficulty of determining the precise truth of such claims, the mine threat will continue to influence commercial shipping operators for some time to come. It would therefore be useful to secure the involvement of European countries ​that have vowed to contribute mine clearance capacity, most notably Belgium, France, Germany, and the Netherlands.

The United States should also welcome the coalition nature of this European-led effort given the resource-intensive nature of convoy and escort missions. This was one of the takeaways from Operation Earnest Will at the end of the Iran-Iraq War. In 1987, Kuwait requested that American warships escort tankers caught in the middle of that conflict, and the U.S. Navy was large enough at the time (around 600 ships) to take on that mission by itself. Yet the Navy’s current fleet is smaller (nearly 300 ships) and lacks the resources to handle such operations for long, so it is in Washington’s interest to support the formation of a like-minded multinational mission.

Recommendations

If the European-led effort is to be credible, the participants will need to put forth concrete details about what operational commitments they are willing to make and what military capabilities they will provide. The difference between the number of attendees at the Paris meeting (51) and the London meeting (around 30) likely indicates that several countries politically support the effort but do not have the capacity to provide substantive military support.

The challenge now is to ensure that this number does not decline further. On the contrary, planners should strive for a force that is perceived as credible enough to draw in additional countries, particularly from Asia. The most recent European Union naval mission in the region—Operation Aspides in the Red Sea, launched February 2024—undoubtedly helped increase commercial traffic through that waterway after Iran’s Houthi partners spent months trying to throttle it. Yet Aspides also highlighted the difficulty of marshalling and deploying sufficient assets to return shipping to normal. After last week’s conference in Paris, most of the countries endorsing the joint British-French statement were European, with the notable exceptions of Australia, Bahrain, Canada, Djibouti, Iraq, New Zealand, South Korea, and Somalia.

If the Trump administration does not wish to directly encourage the European-led effort, it could still serve American interests by avoiding statements that obstruct the mission and potentially deter additional countries from participating in it. This includes ceasing hostile remarks against European nations and officials, which cause gratuitous damage to allied perceptions of Washington. U.S. officials could also help by publicly and privately reinforcing the many other ties and shared interests between coalition participants and the U.S. military. Before that can happen, President Trump must first be willing to move past transatlantic disagreements over the Iran war, which seemingly prompted his negative reaction to the Paris summit.

On a more practical level, U.S. forces will presumably still be in the area once the European-led effort launches. As such, solid transatlantic coordination will be key, including military deconfliction, cooperation on demining activities, and intelligence sharing. These and related topics may come up in President Trump’s discussions with King Charles during next week’s royal visit.