Iran Closes Strait of Hormuz; US-Iran Deal Under Strain
Iran’s Islamic Revolutionary Guard Corps (IRGC) announced on Saturday that it has closed the Strait of Hormuz to all vessels, accusing the United States and Israel of violating the ceasefire deal signed just three days ago. The dramatic escalation comes as mediators in Pakistan confirmed that technical talks between the US and Iran remain scheduled for Sunday in Bürgenstock, Switzerland, raising the stakes for what was already expected to be a pivotal diplomatic moment.
The Strait of Hormuz Closure
The IRGC Navy issued a formal warning Saturday afternoon, telling vessels not to approach the strategic waterway. “Do not approach the Strait of Hormuz; otherwise, your security will be jeopardized,” the Guard said in a statement, according to BBC News. Iran cited what it described as “America’s blatant breach of promise” and Israel’s continued military operations in Lebanon as justification for the move.
However, the US military has directly contradicted Iran’s claim. US Central Command (Centcom) reported that 55 merchant ships transited the strait on Saturday, moving more than 17 million barrels of oil, and stated that “safe passage through the international waterway remained intact.” Vice President JD Vance also told Fox News there was “no evidence” Iran had closed the strait, noting that 16 million barrels of oil had moved through the waterway the previous day.
The Fragile Islamabad Memorandum
The closure announcement threatens to unravel the 14-point Memorandum of Understanding signed Wednesday by President Donald Trump and Iranian President Masoud Pezeshkian at the G7 summit in France. The Islamabad Memorandum had been hailed as a breakthrough to end a war that began on February 28, 2026, when the US and Israel launched coordinated airstrikes against Iran.
Key provisions of the MOU included an immediate termination of military operations on all fronts—including Lebanon—the reopening of the Strait of Hormuz, and a 60-day negotiation period for a final deal. Iran agreed to use its “best efforts” to ensure safe passage through the strait for 60 days without charge, while the US committed to removing its naval blockade within 30 days.
Lebanon Ceasefire Collapse
The immediate trigger for Iran’s announcement was the rapid collapse of a separate ceasefire between Israel and Hezbollah in Lebanon. US officials announced the ceasefire on Friday, but it unraveled within hours. At least 20 people were reportedly killed by Israeli strikes in southern Lebanon within 24 hours, with both Israel and Hezbollah accusing each other of violations.
Iran has consistently insisted that the Lebanon front must be included in any broader peace deal. The first paragraph of the 14-point MOU explicitly calls for “the immediate and permanent termination of military operations on all fronts, including in Lebanon.” Iran’s foreign ministry spokesman, Esmail Baghaei, stated that negotiations for a final agreement will begin only when key commitments—including the cessation of operations in Lebanon—have been implemented.
Trump Reveals Covert Maritime Strikes
In a separate development that has reshaped the narrative around the deal, President Trump revealed details of a covert US naval operation that he says crippled Iran’s military capabilities before the agreement was reached. In an interview with Axios, Trump claimed the US spent nearly two months conducting overnight missions that destroyed 159 Iranian ships, 200 aircraft, and decimated the country’s military leadership.
“Do you know that for the last two months, I’ve been taking many ships out there and nobody knew it?” Trump said, as reported by Fox News. “We’d leave at one o’clock in the morning, all lights off… and they had no equipment because we destroyed all of the equipment that would normally be used to detect this.” Trump described the resulting deal as “probably unconditional surrender.”
Vance Defends Deal Against GOP Critics
Vice President JD Vance pushed back Saturday against Republican critics of the agreement, particularly Senate Armed Services Committee Chairman Roger Wicker, who warned that the $300 billion reconstruction fund for Iran would dwarf the benefits of the 2015 Obama-era nuclear deal. Speaking on Fox & Friends, Vance argued that critics had incorrectly assumed Iran would receive economic benefits regardless of its conduct, as reported by Fox News.
“The United States has all the cards,” Vance said. “There’s a fork in the road here. The United States wins either way, but what ultimately happens from here is very much up to the Iranians.”
Public Opinion and Economic Impact
The diplomatic turbulence unfolds against a backdrop of significant public dissatisfaction at home. A new AP-NORC poll conducted June 11-17 found that 65% of US adults disapprove of Trump’s handling of Iran, with only 28% of Republicans expressing unhappiness. Overall job approval stands at 37%, and 53% of Americans say US military action against Iran has gone too far.
The Strait of Hormuz, through which approximately 20% of the world’s oil passes, has been a central flashpoint throughout the conflict. Oil prices surged to $126 per barrel at their peak, and the disruption has been felt at gas pumps across the United States.
What’s Next
All eyes now turn to Sunday’s technical talks in Bürgenstock, Switzerland, where US and Iranian representatives will meet with Pakistani and Qatari mediators. The Iranian delegation, led by parliamentary speaker Mohammad Bagher Ghalibaf, has departed for Switzerland. Iran has signaled it will demand the US fulfill its commitments under the MOU before entering final deal negotiations.
The key question remains whether the Lebanon ceasefire can be stabilized. As BBC analyst Jon Donnison noted, the deal was “always fragile and torturous in the making” and there are already signs it is unraveling. The coming days will determine whether the Islamabad Memorandum can survive its first major test—or whether the region slides back toward full-scale conflict.