After taking the port of Mokha from Yemen’s Government in Aden, which is internationally recognised, the Houthis continued their advance along the coast on 11 September 2026 and captured the town of Dhubab and Perim Island, locations situated at the narrowest point of Bab el-Mandeb. Four Yemeni government sources told Reuters, while a local administration official told AFP that control over the strait area had now been completed. It is a development that matters for hydrographic reasons before political ones. Perim divides the 32-kilometre-wide Bab el-Mandeb into two corridors: the larger channel, with an average width of 17 kilometres and a depth of more than 180 metres in its central section, and the smaller one, between 2.5 and 5 kilometres wide and with depths of between 21.9 and 28.3 metres, where strong and irregular tidal currents make navigation hazardous. Whoever occupies the island is therefore only a few miles from the trade routes, which can be threatened without the need for long-range weapons. It is the same strategy Iran uses at Larak, in the Persian Gulf.
The Houthis have so far announced no closure of the passage. On the contrary, the Yemeni movement’s political office issued a reassuring statement: “Trade and freedom of navigation in the Red Sea and the Bab al-Mandeb Strait are guaranteed,” Hazam al-Assad said, ruling out the introduction of transit tolls. However, the naval blockade announced in July against Saudi Arabia and vessels linked to it remains in force, amounting to a selective interdiction. On 9 September, on the eve of the fall of Mokha, tracking data counted 28 merchant ships transiting the strait, in line with the average of previous weeks.
The marine insurance market had already recalibrated risk in July, when indicative war-risk premiums rose to 0.75% of the vessel’s value, from 0.3% the day before the blockade was announced. Consultancy Ambrey at the time pointed to a precedent: during the 2024 crisis, the Houthis struck vessels on the basis of corporate links that were no longer current, and the risk of misidentification remains high. The movement’s opponents add a more radical scenario: the mining of the channels, which would require a sizeable international naval force to neutralise.
This escalation comes just as shipping companies are carrying out a gradual return to the Red Sea, and therefore to the Suez Canal, for container ships. MSC has made at least seven eastbound transits through Bab el-Mandeb over two weeks, and on 10 August Maersk and Hapag-Lloyd brought the Gemini alliance’s AE19 service, linking Asia, the Mediterranean, Saudi Arabia and Europe, back through the canal.
Bab al-Mandeb is also important for energy transport. The US Energy Information Administration estimates that 4.2 million barrels per day, including crude oil, condensates and petroleum products, crossed the strait in the first half of 2025, about half the volume recorded in 2023, rising to 8.1 million in the second quarter of 2026. The recovery reflects Saudi Arabia’s decision, after the substantial closure of Hormuz, to shift a growing share of its exports to the Red Sea via the East-West pipeline to Yanbu. But this is the route now being called into question by the coastal offensive. Meanwhile, at Hormuz, transits fell on 9 September to seven vessels from twelve the previous day, compared with an average of fourteen over the previous ten days, with no LNG carriers.
To address the situation, Saudi Crown Prince Mohammed bin Salman called Donald Trump twice, asking for raids against the Houthis as the militia was taking Mokha, but the US president refused direct intervention in the Red Sea, confirming instead the supply to Riyadh of intelligence and targeting data. The United Nations Special Envoy, Hans Grundberg, warned of the risks to freedom of navigation and urged the Security Council to prevent the conflict from spreading beyond Yemen’s borders. Pakistan warned Iran that the continuation of the offensive risks triggering the joint defence agreement linking Islamabad with Riyadh and Ankara.
M.L.
