A commercial tanker was struck by an unknown projectile in the Strait of Hormuz on Saturday, according to the UK Maritime Trade Operations (UKMTO). The captain reported damage to the ship’s bridge, but all crew members were safe and no environmental pollution was detected. The Joint Maritime Information Center (JMIC), run by a naval coalition, subsequently raised the maritime security threat level to “significant” and warned mariners of possible mines. This is the second such incident in two days; on Thursday, a cargo ship was hit by a projectile southeast of Oman, also sustaining bridge damage.

Iranian state media, without confirming a specific attack on the tanker, reported that the Islamic Revolutionary Guard Corps (IRGC) had fired “warning shots” at vessels attempting to use routes not approved by Tehran, and that other ships were now seeking Iranian permission before transiting the Strait. The IRGC Navy separately stated it had targeted US military positions in the region in retaliation for American airstrikes on Iran’s coast. The US Central Command (CENTCOM) said its strikes on coastal military targets were a response to what it described as an Iranian drone attack on a commercial vessel in the Strait. US Vice President JD Vance wrote on social media that Washington had respected the ceasefire agreement and that any resumption of violence would be Iran’s responsibility. A US official, speaking anonymously to the Washington Post, said the administration could easily revoke sanctions waivers if Iran failed to meet its commitments, adding that the waivers strengthened US leverage.

Bahrain and other Gulf Arab states condemned the recent Iranian attack and asserted their right to respond. The International Maritime Organization (IMO) has recorded 46 confirmed incidents in the Strait of Hormuz and surrounding waters up to 11 June, resulting in at least 14 seafarer deaths, and has called for an immediate halt to attacks on commercial shipping. The Strait, through which roughly one-fifth of global oil consumption passes, had been gradually reopening after months of disruption, but the latest escalation threatens that recovery.

The exchange of fire is the most severe since the interim ceasefire and memorandum of understanding (MoU) signed between Washington and Tehran on 17 June. Both sides have repeatedly accused each other of violating the truce. Tehran has charged that the US failed to uphold the ceasefire in Lebanon and has not adhered to the interim agreement, while Washington points to Iranian attacks on commercial navigation. Iran has warned it may suspend technical talks with the US following the American strike on Sirik Island. The JMIC has expanded the southern transit route to accommodate simultaneous inbound and outbound traffic and indicated that naval clearance operations will continue. Investigations into the origin of the projectile are ongoing, and no party has claimed responsibility for the tanker strike.