Amid renewed escalation between the United States and Iran, President Donald Trump says the US will restart its naval blockade of Iran and “become the guardian” of the Strait of Hormuz.
Trump added that the US will charge a 20 percent toll on ships transiting through the strait.
Here is a closer look at what Trump said and what this could mean for ships passing through the Strait of Hormuz.
What did Trump say?
Trump revealed his plans for the Strait of Hormuz in an interview with Fox News and in a post on his Truth Social platform on Monday.
“We are reinstating the THE IRANIAN BLOCKADE, so named because it is only stopping Iran’s ships or customers from entering or leaving,” Trump posted.
The US Navy-led Joint Maritime Information Center subsequently added that the blockade would begin at 20:00 GMT on Tuesday.
“The U.S.A. will be, from this point forward, known as ‘THE GUARDIAN OF THE HORMUZ STRAIT’,” Trump added, “but as such, and as a matter of FAIRNESS, will be reimbursed, at the rate of 20% on all cargo shipped, for any and all costs necessary to do the job of providing safety and security to this very volatile section of the World.”
“The process and formation will begin immediately,” he said.
But Andreas Krieg, a senior lecturer at the School of Security Studies at King’s College London, told Al Jazeera that Trump’s latest comment “looks much more like an improvised political remark than a developed policy”.
“It reflects President Trump’s instinct to demonstrate that he still has leverage and options, even as Washington’s room for manoeuvre has narrowed considerably,” Krieg said. “The problem is that the proposal misunderstands what the dispute over the Strait of Hormuz has become. This is no longer primarily about generating revenue. It is about authority, prestige and who sets the rules of the Gulf’s most important waterway.”
Could Trump’s proposal work?
Krieg said, in practice, he does not see the US-administered 20 percent toll working.
He explained that Washington “has no legal mechanism to impose charges on international shipping through the strait, nor does it physically control the waterway”.
“More importantly, introducing an American toll would inadvertently validate Iran’s own argument that passage through Hormuz is something that can legitimately be monetised. Washington has spent weeks insisting that freedom of navigation is a principle under international law,” Krieg said.
“If it suddenly starts talking about charging for access itself, it weakens its own legal and political position while strengthening Tehran’s narrative that control over Hormuz comes with the right to levy fees.”
What would this mean for ships trying to travel through the strait?
Krieg explained that commercial shipping companies will comply with whoever can actually affect their ability to sail safely.
“They are not choosing between an American toll and an Iranian demand on commercial grounds. They are making risk calculations based on insurance, security and operational continuity,” he explained.
He added: “If Iran continues to exercise coercive control over the strait, shipping companies will adapt to that reality regardless of what Washington announces from the White House.”
Before the war, most commercial traffic in the Strait of Hormuz followed established shipping lanes that run roughly through the middle of the strait.
Now, the vessels face a stark choice: If they move near the Omani side of the strait, they risk getting attacked by Iran, and if they sail closer to Iranian waters in coordination with Iran, they risk being accused of violating Trump’s blockade and could face US attacks.
Krieg said Trump’s proposal would create greater uncertainty for vessels traversing through the Strait of Hormuz.
“Shipping companies already face conflicting guidance from insurers, naval authorities and regional governments,” he said. “Adding a politically driven American toll proposal without any internationally recognised enforcement mechanism would create another layer of legal and commercial ambiguity. Markets dislike uncertainty far more than they dislike predictable costs.”
What does international law say about tolls in waterways?
Arsenio Dominguez, the secretary-general of the United Nations shipping agency, the International Maritime Organization (IMO), told Al Jazeera in April that the introduction of tolls in waterways goes against international law.
“Countries do not have the right to introduce tolls or payments or charges on these straits,” Dominguez said.
“Any introduction of tolls is something that is against international law,” he said.
In a statement on Monday, the IMO said it opposed any imposition of fees to sail through the strait.
“We have always been consistent on our stance on fees. IMO stands firmly against charging fees for passage through straits used for international navigation,” the agency said.
“There is no legal basis through which to introduce mandatory tolls simply to transit through a strait.”
In June, Trump’s secretary of state and national security adviser, Marco Rubio, had rejected the notion of any country charging tolls to pass through international waterways.
“No country is allowed to charge tolls or fees on an international waterway. That’s existing international law,” Rubio said, at the time responding to the possibility of Iran levying fees for passage.
On Monday, Brazilian President Luiz Inacio Lula da Silva described Trump’s plan as “piracy”.
“President Trump tweeted that he will unblock the Strait of Hormuz,” Lula said at an event in Sao Paulo. “But for every ship, the oil owner must pay him 20 per cent. This used to be considered piracy.”
What is the backdrop?
Trump’s renewed blockade comes after a week of renewed hostilities between the US and Iran that has eroded peace negotiations.
The US launched attacks on Iran last week, accusing it of going against the terms they had agreed to pertaining to the Strait of Hormuz during their negotiations. Iran’s Islamic Revolutionary Guard Corps (IRGC) has since launched multiple waves of retaliatory attacks on US military assets in Gulf countries and Jordan.
Krieg said the deeper problem is strategic.
“Every time Washington publicly improvises new ideas without first building an international consensus, it reinforces the perception in Tehran that the United States is searching for leverage because it has run out of military options.
“That encourages the IRGC to hold its position rather than compromise. Ironically, proposals like this make it harder, not easier, to persuade Iran to step back from its increasingly assertive posture in the strait.”