The US military has escalated its maritime enforcement in the Gulf of Oman, firing on a cargo vessel it accused of attempting to breach the naval blockade against Iran. The attack, which targeted the ship's engine room with two Hellfire missiles, marks a significant use of force during a period of relative calm in the ongoing US-Israeli war with Iran. Main Developments US Central Command (CENTCOM) reported that a Navy helicopter fired two Hellfire missiles at the Panama-flagged Vela Nova cargo vessel on Tuesday. The statement said the ship had "attempted to transit the Gulf of Oman and violate the U.S. blockade against Iran by sailing toward an Iranian port." According to CENTCOM, the missiles struck the vessel's engine room and disabled its steering gear, after the crew allegedly ignored "repeated warnings from American forces." The command did not disclose whether any crew members were wounded in the attack. Read also: Egypt Truck Crash Kills 18, Many Children, in Latest Road Tragedy The incident occurred against a backdrop of stalled diplomacy. Attacks have largely paused since a 13-day escalation in July, which followed the apparent collapse of a June memorandum of understanding (MoU) between the US and Iran. That agreement had lifted the blockade and Iran's control over the Strait of Hormuz to facilitate renewed negotiations. Background The US reimposed its naval blockade of Iranian ports and Iran reasserted its control over the Strait of Hormuz after the ceasefire collapsed. The June MoU had been designed to kickstart talks on a more lasting peace, the future of crippling sanctions on Iran, and its nuclear programme. Efforts to revive the agreement have yielded little progress. On Monday, former President Donald Trump appeared to raise the stakes by calling for reparations from Iran for "50 years" of damage. Tehran has previously insisted that reconstruction funding be part of any deal, with the June MoU containing a preliminary plan for a $300bn fund. The conflict has been further complicated by attacks from Yemen-based Houthis on ships in the Bab al-Mandeb Strait, another critical trade route. Iran has focused its diplomatic efforts on direct talks with Oman to determine new shipping lines in the Strait of Hormuz, through which 20 percent of the world's maritime fossil fuel trade transited before the war began on February 28. Why It Matters The strike on the Vela Nova underscores the fragility of the ceasefire and the risks to commercial shipping in a region vital to global energy supplies. With the blockade back in force, any vessel approaching Iranian ports faces the threat of military action, raising the stakes for international trade and regional stability. The incident also highlights the deadlock in US-Iran diplomacy. While the June MoU was meant to pave the way for negotiations on sanctions and Iran's nuclear program, both sides remain entrenched, with Iran demanding changes in US behavior and reconstruction funding, and the US seeking reparations. What's Next Diplomatic efforts continue on multiple fronts. Pakistan's Interior Minister Mohsin Naqvi arrived in Tehran on Tuesday for talks with Iranian officials, part of wider mediation efforts to end the war. Meanwhile, Iran's Supreme National Security Council secretary, Mohsen Rezaei, was quoted by Tasnim news agency as saying the Strait of Hormuz "will not be opened until the United States changes its behaviour and accepts Iran's conditions," adding that any agreement with Oman would be "separate" from the strait's closure. The coming days will likely test whether the relative calm holds or whether further maritime incidents push the conflict back toward full escalation. The fate of the Vela Nova's crew and any potential diplomatic fallout from the attack remain open questions.