Iran Redirects 20 Million Barrels via Covert Offshore Oil Network Amid U.S. Port Blockade, Firm Reports

(SeaPRwire) –   According to maritime intelligence firm Windward AI, Iran is utilizing clandestine offshore networks to transport tens of millions of barrels of oil, circumventing a new U.S. blockade on its ports.

The blockade was implemented on April 13 during a period that included a two-week ceasefire and unsuccessful peace negotiations between the U.S. and Iran, while President Donald Trump maintained that the strategic waterway must stay open. Approximately one-fifth of global oil shipments traverse this route.

Windward informed Digital that “Iranian oil distribution is ongoing via indirect routing and offshore transfer networks.”

The company identified that “as of April 13, a minimum of 11 tankers holding an estimated 20 million barrels of Iranian oil are located off the coast of Malaysia at a ship-to-ship transfer hub.”

“These ships are probably waiting for other vessels to arrive for unloading or are getting ready for further transport,” the firm assessed.

Windward further explained that this gathering of vessels underscores Iran’s “persistent use of offshore storage and transfer methods.”

This strategy enables Iranian oil shipments to “continue without needing to pass directly through the Strait.”

“Covert operations continue to be a fundamental component of current activities, aiding both port calls after transit and wider avoidance tactics,” Windward stated.

“Concurrently, Iranian oil shipments are being directed more frequently through offshore hubs, diminishing the need for direct passage through the Strait of Hormuz.”

U.S. forces started enforcing the blockade at 10 a.m. ET on April 13 after Trump promised to prevent “any and all ships from attempting to enter or leave” the strait, following a period of sustained pressure on Tehran.

As Digital had earlier reported, the U.S. military verified on Wednesday that it had intercepted nine oil tankers trying to violate the blockade.

U.S. Central Command (CENTCOM) stated that “in the initial 48 hours of the U.S. blockade on vessels entering and leaving Iranian ports, no ships have successfully passed U.S. forces.”

“Furthermore, nine vessels have followed instructions from U.S. forces to reverse direction and head back to an Iranian port or coastal region,” CENTCOM posted on X.

was also informed that all nine of these vessels were oil tankers. A senior U.S. defense official said that none of the vessels instructed to turn back required boarding by U.S. forces.

However, on April 14, the first complete day of the blockade under active U.S. patrols, Windward observed ship activity that suggested “a disjointed and inconsistent reaction to the blockade.”

The firm reported that “early movements reveal a mix of continued passage, altered routes, and possible avoidance attempts.”

“Vessels that are sanctioned or sailing under false flags are still operating, with some moving through the Strait while others hold position, turn back, or change their planned routes.

“Iranian oil shipments persist via indirect distribution channels, with large quantities being held offshore instead of moving directly through the Strait of Hormuz.”

CENTCOM clarified that the blockade would only affect maritime traffic coming into or leaving Iranian ports.

It emphasized that U.S. forces would not “disrupt freedom of navigation” for ships passing through the strait en route to other locations.

The blockade on this crucial trade route would be applied “without bias” to all vessels entering or exiting Iranian ports, including those in the Persian Gulf and the Gulf of Oman.

To date, sanctioned vessels and those with false flags are still operating as enforcement measures develop.

Rich Starry, a U.S.-sanctioned handy-size tanker indicating it was fully loaded, continued its outbound journey after having turned around earlier.

Windward noted that the tanker’s course avoided the Larak Island corridor and instead matched an alternative outbound route suggested by Iran.

Simultaneously, Windward also reported observing Murlikishan, a U.S.-sanctioned chemical tanker, traveling inbound.