Houthi Blockade of Saudi Ports Starts Affecting Tanker Routes

Early Signs of Impact From Houthi Threats

According to a report by The Maritime Executive, the recently declared Houthi blockade against vessels calling at Saudi Arabian ports appears to be having its first tangible effects on shipping patterns, even though no actual attacks have been reported in the Red Sea, Gulf of Aden, or nearby waters. At least three tankers are understood to have changed their planned routing, despite none of them being directly threatened.

Vessels Reversing Course

Two of the vessels involved had loaded crude oil at Saudi Arabia’s Yanbu terminal and were heading south through the Red Sea before turning back. The Singapore-flagged VLCC Xin Long Yang (IMO 9761463) is still showing China as its AIS destination, with an arrival estimate of August 10. The Liberia-flagged tanker Rodos (IMO 1024948) has now listed Port Suez as its destination instead. Reaching the Suez Canal as a VLCC typically requires discharging roughly half the cargo at Ain Sukhna into the Sumed Pipeline, transiting the canal lightly loaded, and then taking on the remaining cargo at Sidi Kerir near the pipeline’s northern terminus.

A third tanker, the Hong Kong-flagged VLCC New Prime (IMO 9799123), had been sailing empty toward Yanbu but reportedly reversed direction off Salalah and is now heading east, according to Vanguard reporting cited in the source. Separately, Lloyd’s List Intelligence identified a Chinese vehicle carrier, the COSCO Shipping-operated Liu Jiang Kou (19,000 dwt), making a U-turn in the Gulf of Aden rather than continuing toward the Red Sea. These course changes are believed to be linked to a threat the Houthis issued on July 20.

Warnings Sent, But Not Publicized

The course alterations followed generic warning emails distributed to a number of shipping companies by the Houthi Humanitarian Operations Coordination Center (HOCC) — the body that has previously acted as a point of contact for merchant vessels transiting Yemeni waters. Notably, the HOCC’s own website has not published the warning that was sent by email, a departure from how such notices have been handled in the past.

Despite these individual diversions, overall traffic through the IMO-designated Maritime Transit Security Corridor across the Gulf of Aden and southern Red Sea does not appear to have dropped. In fact, informal observation suggests volumes on July 21 were somewhat higher than five days earlier, on July 16.

Political Backdrop

The blockade is tied to broader regional tensions. It is said to partly support Iran’s Revolutionary Guard, which is facing mounting pressure amid a worsening situation around the Strait of Hormuz. But the more immediate trigger appears to be a dispute over flight access to and from Yemen, following the blocking of a return flight carrying mourners from the funeral of the late Iranian Supreme Leader Ali Khamenei — a flight that was diverted to land at Hodeida rather than Sana’a. This dispute is intertwined with stalled negotiations among the Houthis, Saudi Arabia, and the internationally recognized Yemeni government over a final settlement to the civil war that began in 2014, with the Houthis reportedly seeking a $13 billion payment from Saudi Arabia as part of any deal.

What It Means for Owners and Charterers

For ship operators, this situation underscores how quickly commercial routing decisions can be driven by threats alone, well before any physical attack occurs. Rerouting a VLCC away from Yanbu, or opting for the costlier ship-to-pipeline-to-ship transit around Suez, carries real cost and schedule implications, even in the absence of confirmed violence. Owners and charterers with cargo moving to or from Saudi terminals should treat these diversions as an early warning signal rather than an isolated event, and factor contingency planning — including alternative discharge or loading points — into voyage instructions. For vessels that do continue transiting affected waters, this is also a moment to ensure documentation, bunker quantities, and cargo condition are properly verified before and after any unplanned course change, since diversions and extended transits can affect fuel consumption records and cargo integrity in ways that later become relevant to claims or charter party disputes. Independent verification through bunker surveys or cargo inspections can help owners and charterers establish a clear record if a voyage is disrupted or rerouted under threat conditions.

As of this reporting, the situation remains fluid, with no confirmed attacks but a clear pattern of precautionary rerouting emerging among vessels calling at, or transiting near, Saudi Red Sea ports.

Reviewed by Ibrahim Halil Ceylan, Marine Surveyor at Apeks Marine.