Shipping activity through the Bab el-Mandab Strait rose sharply on Tuesday, July 28, reaching its highest level since July 19. The increase signals a partial resumption of commercial traffic, but not a full restoration of confidence, as major energy carriers continue to avoid the route and evidence grows that access to the southern Red Sea is becoming increasingly selective.

Kpler ship-tracking data showed 37 commodity and energy vessels transiting the strait on Tuesday, compared with only 11 on Sunday. Twenty vessels entered the Red Sea, while 17 sailed out toward the Gulf of Aden and the Indian Ocean. 

Among the outbound vessels were three Aframax crude tankers. The Aisopos and Gustav were each carrying more than 750,000 barrels of oil, while the Karachi was transporting approximately 430,000 barrels toward Pakistan. Two inbound tankers were carrying petrochemical products and chemicals toward destinations north of the Suez Canal and in Turkey.

Despite the higher overall number, no very large crude carriers, or VLCCs, and no liquefied natural gas carriers were recorded among Tuesday’s transits. Their absence suggests that owners and charterers of the largest and most valuable energy cargoes remain unwilling to treat Bab el-Mandab as a fully reliable shipping route.

Partial Recovery, Not a Return to Normal

The rise from 11 to 37 vessels indicates that part of the traffic previously delayed or diverted has resumed. However, the movement remains highly calculated and concentrated among vessels whose operators appear prepared to accept the security risks or have obtained sufficient assurances to proceed.

Several factors continue to prevent a broader recovery: the absence of VLCCs and LNG carriers, continued Houthi threats and attack claims, the diversion of some tankers away from the strait and growing indications that certain vessels are securing individual passage arrangements.

The result is an increasingly uneven operating environment. Bab el-Mandab remains physically open, but passage is no longer governed solely by ordinary commercial schedules and maritime regulations. Political relationships, cargo origin, vessel ownership and access to informal assurances are becoming important factors in determining whether a ship proceeds or changes course.

New Incident in the Southern Red Sea

The increase in traffic coincided with another security incident in the southern Red Sea. According to UK Maritime Trade Operations, the master of a tanker reported hearing an explosion while the vessel was transiting the area.

No damage to the tanker, injuries to the crew or marine pollution were reported. The source and nature of the explosion were not immediately established.

The incident illustrates the uncertainty surrounding current maritime operations. Even when ships are not directly hit, nearby explosions, suspected projectiles and unverified attack claims can influence routing decisions, insurance assessments and crew security procedures.

It also came amid a Houthi claim that the group had targeted the Saudi oil tanker NCC GHAZAL with multiple ballistic missiles and forced it to retreat.

A Sheba Intelligence investigation found no independent evidence supporting the claim at the time of publication. UKMTO, international maritime security organisations, Saudi authorities and shipping agencies had not reported an incident involving the tanker. An open-source timeline prepared by Sheba Intelligence also showed the vessel maintaining normal movement before the Houthi announcement, without a publicly visible distress signal, emergency manoeuvre or major change in speed or direction. 

While incomplete or delayed AIS transmissions cannot conclusively rule out an attempted attack, the available evidence did not confirm that the vessel was struck or forced to reverse course.

China Pursues Vessel-by-Vessel Clearances

The selective nature of current traffic is most clearly demonstrated by China’s reported contacts with the Houthis.

Reuters reported that Beijing has been communicating directly with the group to secure the passage of tankers carrying Saudi oil to China. Rather than establishing a general arrangement for all Chinese shipping, clearances are reportedly being discussed separately for each vessel. Iran has also been involved or informed in relation to some of the contacts. 

Four tankers carrying Saudi crude toward China have passed through Bab el-Mandab since the Houthis announced their maritime blockade against Saudi-linked shipping. Other vessels, however, have altered their routes. The VLCCs New Champion and New Prime were among the tankers that turned away from the southern Red Sea because of continuing security concerns.

These developments suggest that the declared Houthi blockade is evolving from a broad public threat into an informal selective-passage system. Under this emerging arrangement, a vessel’s nationality, cargo, destination, ownership structure and the political relationship of the importing state may determine whether it is threatened, tolerated or granted prior assurances.

Reuters Reporting Reinforces an Earlier Sheba Intelligence Exclusive

New information published by Reuters that the Houthis are considering charging commercial vessels for passage through the Red Sea closely aligns with findings disclosed by Sheba Intelligence three days earlier.

Sheba Intelligence had reported that internal discussions included proposals to obtain financial contributions or other forms of support from certain vessels in return for facilitating their passage. The discussions reportedly focused in particular on ships whose ownership structures or commercial affiliations were unclear.

The proposals had not been formally adopted when Sheba Intelligence published its report. Nevertheless, the discussions indicated that the Houthis were exploring ways to derive financial and political benefits from maritime control beyond their immediate military objectives.

Reuters subsequently reported that the group was considering establishing fees for commercial vessels sailing through Bab el-Mandab. The discussions reportedly involved Iranian officials and included the possibility of creating an authority to regulate and implement the proposed payment system. Chinese vessels were expected to receive exemptions as a result of Beijing’s direct contacts with the group. 

The new reporting therefore reinforces the earlier Sheba Intelligence disclosure and suggests that the proposals under discussion are broader than isolated informal payments. They may form part of an attempt to institutionalise an unofficial maritime passage regime.

Houthi Blockade Centre

The development is consistent with an earlier Sheba Intelligence exclusive concerning the activation of a Houthi maritime blockade centre following the announcement of the ban on Saudi-linked shipping.

According to the report, the centre was tasked with managing targeting lists, monitoring vessel movements, issuing warnings to shipowners, operators and charterers, and processing requests from vessels seeking assurances or safe passage.

Such a structure would allow the Houthis to move beyond launching missiles and drones toward administering an informal system of maritime access. Under this model, military threats create the pressure, while the blockade centre determines which vessels may pass, which require further scrutiny and which could be targeted.

The reported Chinese negotiations, individual vessel clearances and discussions about collecting payments all correspond with the operational framework previously described by Sheba Intelligence.

Two Distinct Maritime Threat Zones

Commercial vessels crossing the wider region currently face two different but overlapping threat environments.

In the eastern Gulf of Aden and waters closer to Somalia, the primary risks include piracy, suspicious approaches by small boats, armed boarding and attempted seizure.

In the western Gulf of Aden, Bab el-Mandab and the southern Red Sea, the main threats are missiles, drones, nearby explosions and Houthi warnings connected to the declared blockade.

Shipping companies must therefore prepare for a single voyage to pass through two separate security zones: an eastern area dominated by piracy and armed boarding risks, and a western area shaped by military attacks, political targeting criteria and informal passage arrangements.

Assessment

Tuesday’s increase in traffic shows that the Houthi blockade has not closed Bab el-Mandab. It does not, however, represent a return to normal maritime conditions.

The continued absence of VLCCs and LNG carriers, the rerouting of some tankers, recurring security incidents and the negotiation of individual passage approvals all indicate that shipping remains selective and vulnerable to political interference.

The more significant development is the apparent transition from an openly declared blockade toward an informal system of controlled passage. Under this emerging model, the Houthis could use the threat of attack to influence which ships transit, negotiate exemptions with individual states and potentially extract financial or political concessions.

The latest Reuters reporting strengthens Sheba Intelligence’s earlier findings that the Houthis are seeking to turn maritime escalation into a more permanent instrument of control and leverage in the Red Sea and Bab el-Mandab.