Ship traffic is gradually returning to the Strait of Hormuz following a temporary agreement between Iran and the United States, but the waterway’s long-term future remains deeply uncertain. Disputes over who controls the strait and whether ships will be forced to pay fees to pass through it are already threatening to complicate negotiations toward a permanent peace deal.
Tensions flared again this past weekend when Iran announced it had reclosed the strait, pointing to Israel’s most recent strikes on Lebanon as justification. The U.S. quickly pushed back on that claim. Maritime tracking data showed that dozens of vessels made the crossing on Saturday and Sunday — though the numbers were still far below what was typical before the conflict began.
President Donald Trump floated the idea that the U.S. could impose its own tolls on ships passing through the strait if a final agreement with Iran isn’t reached within the countries’ 60-day negotiating window. Before the war, passage through the strait was free. Iran, however, created a new governmental body last month — the Persian Gulf Strait Authority — to collect fees from vessels, and has indicated it still expects ships to register with that authority.
No single nation owns the Strait of Hormuz, which runs along the coastlines of both Iran and Oman. A memorandum of understanding reached last week gave Iran temporary authority to manage the strait while talks continue with Oman and six other Gulf nations about how the waterway will be governed going forward. As part of that arrangement, Iran agreed not to charge tolls for 60 days.
Legal experts and maritime industry groups have repeatedly warned that a toll system would break with decades of established international trade practice. Even if the U.S. and Iran reach a final agreement, analysts say it could take months before the flow of oil, natural gas, fertilizer, and other goods returns to pre-war levels.
Data and analytics firm Kpler confirmed that 71 ships traveled through the strait between Friday and Sunday, with the highest single-day count being 35 crossings on Saturday. Before the U.S. and Israel launched strikes on Iran in late February — and before Tehran responded with its own attacks and effectively shut the waterway — roughly 100 to 130 vessels made the trip each day.
Under the terms of the provisional framework, Iran committed to completing demining operations within 30 days and removing what the agreement called “technical and military obstacles” to shipping. Iran’s lead negotiator and parliament speaker, Mohammad Bagher Qalibaf, told Iranian state media on Monday that his country would manage the strait in line with international maritime law.
The strait’s main central route remains mined and closed. Ships have been rerouting through a smaller northern passage that runs through Iranian waters or a southern route through Omani waters. Kpler noted that caution remains evident, with many vessels either following Iran’s designated route or turning off their transponders to hide their locations and identities.
Early in the conflict, Iran began screening ships and demanding payment before allowing them through — a practice shipping analysts called a “tollbooth” arrangement. In early April, Iran formally demanded the right to collect tolls as a condition for loosening its grip on the strait.
Although the Trump administration imposed sanctions on the Persian Gulf Strait Authority late last month — with Treasury Secretary Scott Bessent describing Iran’s actions as an attempt to extort global maritime trade — the president suggested on Saturday that the U.S. might charge its own fees for what he called “services rendered as the Guardian Angel to the countries of the Middle East.” The administration has not explained how any such U.S.-imposed charges would actually work if negotiations break down.
Shipping analysts have expressed surprise at how much authority the initial agreement handed to Iran. “Almost all the power goes into Iran to determine the arrangements going forward in the future. This is what we really need clarity on,” said Philip Belcher, marine director of Intertanko, a trade association for independent tanker owners, speaking Thursday.
Charging tolls in the strait would likely conflict with one of international maritime law’s foundational principles: the freedom of peaceful navigation. That right was formally established through the United Nations’ Convention on the Law of the Sea, which entered into force in 1994. The treaty guarantees ships the right to unobstructed “transit passage” through more than 100 straits around the world, including the Strait of Hormuz. Importantly, this protection applies only to natural waterways — fees can legally be charged for man-made passages like the Panama Canal and the Suez Canal.
Oman is among more than 170 countries that have ratified the U.N. convention. The U.S. and Iran have not, though maritime associations argue that all nations are still bound by its provisions.
James Kraska, a professor of international maritime law at the U.S. Naval War College and a visiting professor at Harvard Law School, points out that both the U.S. and Iran belong to the International Maritime Organization — the United Nations agency responsible for shipping safety and security — and are both parties to the International Convention for the Safety of Life at Sea. In straits like Hormuz, he said, fees may only be collected at designated ports of entry or for services a ship specifically requests, such as specialized navigation assistance through dangerous waters.
“If Iran wants to apply those to everybody, then it has to adjust the traffic separation scheme rules, and that can only be done through the member states of the International Maritime Organization,” Kraska said.
“You can’t impose fees for a ship exercising its right of transit passage,” he added. “So the bottom line is, no — fees in this context are just not lawful.”
Kraska noted that countries have previously worked together to share the costs of maintaining a strait. As one example, Indonesia, Malaysia, and Singapore collaborated with the International Maritime Organization and other nations on a cost-sharing arrangement for the Strait of Malacca — but that model relied on negotiated contributions from the states using the passage, not charges levied on individual ships.
The situation in the Strait of Hormuz has shifted rapidly throughout the conflict. While the outlook has improved since both countries agreed to extend their ceasefire, Marcus Baker, global head of marine, cargo, and logistics at insurance brokerage and risk management firm Marsh, said there remains “a degree of nervousness around the situation.”
Baker said there is strong insurance support for ship owners trying to move cargo during this period, but he cautioned that the interim deal between Iran and the U.S. does not guarantee the strait will remain toll-free once the negotiating window closes. “We’ll see what the next six weeks brings us,” he said.
