Strait of Hormuz ship transits – two routes, two sets of rules

Vessels in the Strait of Hormuz either transit via northern route which requires approval from Iran taking 48 hours or the freedom to sail at any time through the southern route in Omani waters, but with a possible threat of mines.

The Memorandum of Understanding (MoU) between the US and Iran and a resulting 60-day ceasefire sees the Strait reopening but in a far from a unified manner with the international traffic separation scheme (TSS), believed to have been mined by Iran, remaining closed. On 19 June Iran moved to exert authority over the waterway issuing details of a system requiring owners to apply for a permit to transit with a waiting time of 48 hours. The Persian Gulf Strait Authority (PSGA) stated: "No vessel is permitted to pass through the Strait of Hormuz without a valid passage permit issued by the PGSA."

The permit mandates using the northern route just to the south of Iran’s Larak Island and the PGSA said use of alternative routes is strictly prohibited.

However, the on 20 June the Joint Maritime Information Centre (JMIC) issued new guidance for the southern route in Omani waters the allows for transit at any time.      “Mariners are advised that they may transit the southern route day or night with their AIS on, radars radiating, running lights on, and normal use of VHF,” the notice said. Ship masters were strongly encouraged to communication and coordination with US NCAGS (Naval Cooperation and Guidance for Shipping), however, it is not mandatory to do so, and ships can transit the southern route without coordination.       However commercial shipping was also warned of the presence of mines and to expect a naval presence undertaking mine clearance. “Mariners should also expect congestion through transit routes and potential VHF hailing from naval forces to support free flow,” the JMIC said.      It leaves a confusing picture for shipowners and managers as transits over the Strait of Hormuz start to rise following the agreement between the US and Iran. A number of transits were shown on AIS from Pole Star Global late 19 June/early 20 June local time via the Iranian route. These included the Indian-flagged VLCCs Desh Vibhor and Desh Viabhor, and a Chinese-flagged bulker Hai Tun Zhou.