The United States says no vessel succeeded in passing its blockade of Iranian ports during the first 24 hours of the operation.
According to US Central Command, six merchant vessels complied with instructions from US forces and turned around to re-enter an Iranian port in the Gulf of Oman.
The blockade on all vessel traffic entering and leaving Iranian ports began at 14:00 UTC on 13 April.
Two vessels, the Malawi false-flagged Rich Starry and the Comoros-flagged Elpis, crossed the Strait of Hormuz on 14 April. However, once they reached the Arabian Sea, both either turned around or halted, apparently after encountering the US naval blockade, which is believed to have assets deployed in the Arabian Sea.
United Against Nuclear Iran said it tracked at least four tankers making U-turns, including Manali and Christianna, in addition to Rich Starry and Elpis.
At the same time, the OFAC-sanctioned VLCC Alicia, sailing under a Curacao false flag, passed through the Gulf of Oman and the Strait of Hormuz on 14 and 15 April and is now in the Arabian Gulf broadcasting a destination of “for orders”, according to tracking data from Pole Star Global. The vessel had arrived in the region from Malaysia’s Eastern Outer Port Limits, an area associated with ship-to-ship transfers of sanctioned Iranian crude bound for China.
US Central Command said more than 10,000 US marines, sailors and airmen are involved in the blockade operation, supported by more than a dozen warships and dozens of aircraft.
The measure is being enforced against all ships entering or leaving Iranian ports, regardless of flag or nationality. At the same time, the US said it continues to support freedom of navigation for vessels transiting the Strait of Hormuz to and from non-Iranian ports.
An audio recording circulating in maritime circles, purportedly containing a US Navy warning, says ships attempting to breach the blockade could face the use of force. According to the recording, vessels travelling to or from Iranian ports would be subject to interdiction and seizure.
Washington announced the blockade after peace talks between the US and Iran, mediated by Pakistan over the weekend, failed.
Iran has effectively closed the Strait of Hormuz to international commercial maritime traffic since 28 February. Although a 14-day ceasefire created expectations of a reopening, only a small number of vessels have reportedly been allowed through by Iranian authorities, and only after the payment of a toll equivalent to $2m for a loaded VLCC.
Despite the conflict, Iran has continued exporting crude via the Strait of Hormuz. United Against Nuclear Iran said the country exported 1.15m barrels per day in March, about half the level seen in February before the conflict. Of that total, 1.14m barrels per day were shipped to China, with an estimated value of $3.63bn.
