Houthi seizure of Red Sea islands tightens grip on vital artery

Houthi rebels have seized several islands in the Red Sea and the Bab al-Mandeb Strait, a lightning offensive that cements the Iranian-backed group’s control over a vital global shipping artery and has sent fresh shockwaves through energy markets. The militants took Perim Island, which splits the strait in two, along with Zuqar and Hanish islands further north, after capturing the port of Mocha on Yemen’s western coast. The advance effectively places the entire waterway through which a significant share of the world’s maritime trade passes under Houthi authority.

The strategic significance is hard to overstate. Bab al-Mandeb connects the Red Sea to the Gulf of Aden and the Indian Ocean, and it has become a critical route for Saudi oil exports since Iran throttled shipping through the Strait of Hormuz earlier this year. With the islands now in rebel hands, the Houthis can monitor and, if they choose, interdict traffic through the strait from multiple vantage points. A Yemeni analyst who has spoken with government officials said the rebels are now fully in control of the waterway, noting that once Mocha fell, the islands facing it followed. The capture of Perim Island is particularly consequential: the island sits in the middle of the strait, and its possession allows the Houthis to dominate both shipping lanes.

The offensive also signals a deeper problem for the Saudi-backed coalition that has fought the Houthis since Riyadh intervened in Yemen’s civil war in 2015. Analysts point to indications that the anti-Houthi alliance of Yemeni factions is crumbling and faces an uphill battle to counter the rebel advance. One risk advisory firm founder observed that the Houthis now control the entire Red Sea coastline and have added roughly 130 kilometres of coastline over the past 48 hours, including all the main Yemeni islands. The speed and scale of the gains suggest the rebels are operating with a level of coordination and momentum that the coalition has been unable to match.

The implications extend well beyond Yemen’s borders. The offensive deals a significant blow to Saudi Arabia, which has backed the internationally recognised Yemeni government since the Houthis seized the capital Sana’a and ousted it in 2014. It also bolsters Iran’s broader campaign against the United States, part of which has involved pushing up energy prices. Brent crude traded under 105 dollars a barrel on Friday after earlier climbing toward 110 dollars, reflecting the market’s nervousness about supply disruptions in a region already strained by the war with Iran.

The Houthis have compounded the pressure on Riyadh by escalating their attacks on Saudi energy infrastructure. This week alone, the rebels launched waves of missiles and drones at Saudi energy facilities and a military base, wounding more than 70 people and causing damage to oil sites. The Saudi energy ministry has not identified which facilities were hit or the scale of the damage. The kingdom has been forced to rely on a pipeline from its oil-rich eastern provinces to the Red Sea coast to export crude since Hormuz traffic was disrupted, but its oil production fell to 6.2 million barrels a day in August, its lowest level this year. Satellite imagery from September 10 showed a plume of thick black smoke over Medina province, through which the pipeline runs, though the cause was not immediately clear.

The conflict, which had been largely dormant since a ceasefire in 2022, has now reignited in earnest. Saudi Arabia has launched more than 100 air strikes on Yemeni provinces under Houthi control, including at least two attacks on Mocha airport. The Houthis, for their part, claim the strait is safe for all shipping except Saudi vessels, a message designed to reassure commercial traffic while isolating the kingdom. The trajectory of the war, however, points toward further escalation rather than de-escalation. The Houthis have demonstrated both the capability and the will to seize territory that matters to the global economy, and their position along the Red Sea coast now gives them leverage that no amount of air power has so far been able to erode. For energy markets and the shipping industry, the risk is no longer hypothetical: the artery that connects the Mediterranean to the Indian Ocean is increasingly under the control of a belligerent actor with explicit aims against a major oil producer.