About 20 cargo ships began moving towards the Hormuz Strait on the evening of 17/4, following Iran's announcement of the shipping lane's reopening, according to data from civilian maritime tracking site Marine Traffic. This marked the largest group of vessels attempting to transit the area since Iran largely closed the strait in late February in response to the US-Israel attack campaign.

However, these ships quickly halted, with some even turning back for reasons yet unknown. Among them were three container ships from French shipping group CMA CGM, which declined to comment.

By early this morning, most of these vessels had turned back.

Satellite image shows ships near Dubai in the Persian Gulf on 17/4. *Photo: Reuters*

Following this, tracking data indicated that new ships, primarily oil tankers, were continuing to head towards the Hormuz Strait.

Nils Haupt, spokesperson for German shipping group Hapag-Lloyd, which had vessels stranded in the Gulf, told AFP that Hormuz's reopening was "generally good news." However, he stressed that shipping companies require detailed information on potential routes and movement order, citing mine concerns.

"One thousand ships cannot immediately enter the strait; that would cause chaos," he stated. "Iran needs to provide clear information. We will be ready to depart if some questions are answered this weekend."

A ship in the Hormuz Strait, off the coast of Musandam province, Oman on 12/4. *Photo: Reuters*

The Norwegian Shipowners' Association reported that several issues remain unresolved, including mine clearance, Iran's conditions, and practical enforcement.

The shipping group BIMCO advised members against rushing through the strait, citing the threat of mines. A US Navy warning, seen by Reuters, also highlighted the danger these weapons pose.

Matt Wright, a senior shipping analyst at data analytics firm Kpler, noted uncertainty regarding which routes ships can use to exit the Gulf.

Movement route (gray) and danger zone, suspected of having mines (red) in the Hormuz Strait announced by the Islamic Revolutionary Guard Corps (IRGC) on 9/4. *Photo: IRGC*

Bloomberg data from 16/4 indicated approximately 770 commercial ships with active transponders in the Persian Gulf, including about 360 oil and gas tankers. Before the US - Israel and Iran conflict erupted, an average of about 120 ships transited the strait daily, according to Lloyd's List.

A senior Iranian official told Reuters that all commercial ships, including US-flagged vessels, could transit the Hormuz Strait, but their journey must be coordinated with the Islamic Revolutionary Guard Corps (IRGC). Iran would also limit vessels to shipping lanes it deemed safe, while military ships remained prohibited.