Iran's Islamic Revolutionary Guard Corps announced it was closing the Strait of Hormuz and warned commercial ships to stay away, just days after Tehran signed a memorandum of understanding with Washington that committed Iran to keeping the waterway open.
The IRGC Navy issued a statement declaring vessels' "safety would be at risk" if they approached the strait, while Iran's top joint military command, cited by the semiofficial Mehr news agency, described the closure as the "first step" in response to what it called "breaches of commitments by" the United States and Israel. The stated trigger: Israeli airstrikes on Lebanon.
U.S. Central Command pushed back immediately. Capt. Tim Hawkins, a CENTCOM spokesperson, told the Associated Press flatly: "Iran does not control the Strait of Hormuz." He added that traffic continues to flow and American forces are monitoring the situation.
The IRGC's announcement landed after the release of a U.S.-Iran memorandum of understanding signed this week. President Trump signed a copy during a dinner at the Palace of Versailles. Iran's President Masoud Pezeshkian signed remotely.
The MOU's first point could not have been clearer. It declared "the immediate and permanent termination of military operations on all fronts, including in Lebanon," and committed both sides to "refrain from the threat or use of force against each other" while "ensuring the territorial integrity and sovereignty of Lebanon."
A separate provision committed Iran to "make arrangements using its best efforts for the safe passage of commercial vessels, with no charges for 60 days only, from the Persian Gulf to the Sea of Oman, and vice versa."
The path to that agreement was long and volatile. Trump canceled scheduled strikes on Iran in mid-June, signaling that a deal was within reach.
Days later, the president declared the agreement had been approved at the highest levels. And Vice President Vance confirmed the ceasefire memorandum had already been signed digitally ahead of a planned Geneva ceremony.
Now, within the same week the ink dried, Iran's military arm moved to shred the deal's most consequential provision, free passage through the world's most important oil chokepoint.
The gap between Washington's optimistic framing and conditions on the water is stark. Newsmax reported that roughly 80 Iranian-laid naval mines remain in or near primary transit routes through the Strait of Hormuz. Daily transits have recovered to only about 25 vessels per day, compared with a pre-crisis baseline of 125 to 140 ships daily. Nearly 600 vessels remain anchored in the Gulf since February.
Phil Belcher, marine director at the tanker trade association Intertanko, put it bluntly: "The main route... through the middle of the Strait of Hormuz, that's closed, that's dangerous." Richard Meade, editor-in-chief of Lloyd's List, was equally direct: "We are in uncharted territory. I don't think [shipping in the strait] is getting back to normal this year."
The Washington Examiner reported that approximately 20 million barrels of crude oil and oil products pass through the strait daily under normal conditions, roughly 20 percent of global oil demand. National average gas prices were already at $2.98 per gallon and could cross $3.00 within days. Analysts at Rapidan Energy Group and Rystad Energy warned of further price jumps if tensions persist.
That is the economic reality behind Iran's announcement. A closure, even a partial or performative one, sends shockwaves through energy markets that American consumers pay for at the pump.
President Trump responded on Truth Social with a post that addressed the toll question directly:
"There will be NO TOLLS in the Hormuz Strait for 60 days during the Cease Fire Period, and there will be NO TOLLS after the 60 day period has expired, unless they are imposed by and for the United States of America, should the deal not be completed, for services rendered as the Guardian Angel to the countries of the Middle East for purposes of both past, present, and future reimbursement of costs."
The post mirrored the MOU's 60-day safe-passage window but went further, asserting that any future tolls would be imposed by and for the United States, a framing that treats American military presence in the region as a service deserving compensation. Trump had previously declared that Iran accepted all U.S. terms, including the reopening of the strait and an end to uranium enrichment.
Whether the IRGC's announcement represents a genuine military closure or a political signal aimed at domestic and regional audiences remains an open question. CENTCOM says traffic is still moving. But the IRGC's statement, combined with the mine-laden shipping lanes and the plunge in daily transits, makes clear that the strait is far from operating normally, regardless of what any memorandum says.
The sequence of events follows a pattern that has defined the broader U.S.-Iran confrontation. The IRGC declared the strait "effectively closed" earlier this year following U.S. and Israeli strikes on Iran under what was described as "Operation Epic Fury." Iran's Revolutionary Guard gunboats fired on a tanker and an unknown projectile hit a container vessel in the strait after Trump declared the U.S. blockade of Iranian ports would remain in full force.
Iranian Deputy Foreign Minister Saeed Khatibzadeh accused the Americans of "risking the global economy through these, I can say, miscalculations." Trump's response at the time was characteristically direct: "They can't blackmail us."
Then came the diplomatic track. Trump pulled back from planned strikes. Negotiations moved forward. The MOU was signed. Iran committed to reopening the strait.
And now, citing Israeli strikes on Lebanon, strikes the MOU was supposed to end, the IRGC reversed course. Iran's negotiating team was reported to be departing for Switzerland even as the military command announced the closure. Trump had brushed off Senator Lindsey Graham's concerns about the Iran deal at the G7 just days earlier.
Several critical questions hang over this latest escalation. What specific Israeli strikes on Lebanon triggered the IRGC's response, and did they violate the MOU's terms or precede it? What "breaches of commitments" does Iran's military command claim to have identified, and are they citing actions that occurred before or after the deal was signed?
Is the strait physically blocked, or is this an announcement without operational teeth? CENTCOM says traffic flows. The mine count and vessel data say otherwise. The answer matters enormously for global oil prices, shipping insurance rates, and the credibility of any future deal.
And perhaps most importantly: if Iran can sign a memorandum of understanding committing to "immediate and permanent termination of military operations on all fronts" and then order the IRGC to close the world's most important shipping lane within the same week, what exactly is the memorandum worth?
The MOU's language was sweeping. It promised permanent peace, Lebanese sovereignty, and free commercial passage. The IRGC's announcement treated all of it as conditional, contingent on Israeli behavior that Iran's military, not its diplomats, would judge.
This is the fundamental problem with agreements that depend on the good faith of a regime whose military and diplomatic wings operate on different tracks. Iran's foreign ministry sends negotiators to Switzerland. Iran's Revolutionary Guard closes a waterway. Both claim to speak for the same government.
American consumers, Gulf shipping crews, and allied nations in the region are the ones left to sort out which Iran showed up on any given day.
Deals mean nothing if one side treats the signature as a suggestion. The IRGC just made that point more clearly than any critic could.