Iran declared the Strait of Hormuz closed on Saturday, citing continued Israeli military strikes in southern Lebanon as a violation of commitments made under the recent US-Iran memorandum of understanding. The declaration came days after both countries signed an interim peace agreement in which Iran had committed to allowing free passage of commercial vessels through the waterway for 60 days.

The US Central Command disputed the claim, saying 55 merchant ships transited the strait on Saturday and moved more than 17 million barrels of oil to global markets without incident. Iran’s joint military command stated that the closure was a response to what it described as ongoing Israeli operations in Lebanon and a failure by the United States to fulfill its obligations under the truce framework.

The situation marks the latest complication in an agreement signed on June 17 at the Palace of Versailles. Vice President JD Vance had been scheduled to travel to Switzerland for follow-up nuclear talks, but that trip was cancelled as tensions escalated over the Lebanese ceasefire dispute. Switzerland also confirmed that the planned negotiations had been postponed.

Oil markets reacted cautiously to the conflicting statements. Prices, which had fallen sharply after the initial peace agreement was signed, held near recent lows as traders assessed whether the strait was actually blocked to commercial traffic. The two sides gave contradictory accounts of the actual situation on the water.

The Hormuz agreement had been seen as a stabilizing step after weeks of military confrontation. The terms of the memorandum of understanding, signed in Paris, stipulated a 60-day window for Iran to allow shipping through the strait while both sides negotiated on Iran’s nuclear program and broader regional arrangements.

The Israel-Lebanon ceasefire has been fragile since it was agreed. Iran’s decision to link its Hormuz commitments to Israeli behavior in Lebanon introduces new complexity into what was already a multilateral diplomatic challenge. The US-Iran nuclear talks that Vance was meant to open in Switzerland now have no confirmed new date. A full assessment of the situation on the strait is available from US Central Command.