Iran's Islamic Revolutionary Guard Corps has warned commercial vessels to only use Strait of Hormuz routes approved by Tehran, raising tensions in fragile US-Iran negotiations over the waterway, reports Al Jazeera.

The warning followed Oman's announcement of a new shipping corridor coordinated with the International Maritime Organization. Hours later, the 9,466 TEU Ever Lovely, a Singapore-flagged ship, was struck off Oman's coast while travelling along the Omani-approved route. Reuters cited US officials blaming Iran for the attack.

Evergreen, the vessel's owner, said all crew and cargo were safe. The incident highlights unresolved issues in the memorandum of understanding signed by Washington and Tehran, which halted hostilities in the US-Israel war on Iran and launched a 60-day negotiation process.

Both sides have declared the strait open to commercial shipping, but questions remain over whether Iran will impose transit fees or seek greater control of vessel movements. Analysts warn disagreements could derail efforts to reach a permanent peace deal.

The Strait of Hormuz carries about one-fifth of global oil and liquefied natural gas shipments, as well as one-third of fertiliser trade. In 2025, about 20 million barrels of oil and petroleum products passed through daily, according to the US Energy Information Administration.

The IRGC said the new corridor was announced without consultation and posed "serious safety risks." It insisted only routes designated by Iran are authorised and that ships must maintain contact with its navy while transiting. In April, Iran issued its own map requiring vessels to pass closer to its coast.