Iran-backed Houthi forces advanced to Perim Island on September 11, 2026, tightening control over the Bab el-Mandeb Strait. The offensive, which followed the capture of Yemen’s port city of Mokha, threatens a vital global shipping corridor and pushes regional crude benchmarks past $100 per barrel amid widening conflict.
The strategic geography of the southern Red Sea shifted dramatically on September 11, 2026, as fighters loyal to the Houthi movement reached the island of Perim in the Bab el-Mandeb Strait according to four Yemeni government sources. The advance came just one day after the Houthis seized Yemen’s port city of Mokha, delivering a severe setback to Saudi Arabia and the internationally recognized government it supports.
The Fall of Mokha and Perim Island
Local officials confirmed that government forces had pulled out of Perim Island and the mainland coastal town of Dhubab, which faces the island across the narrow waterway.
Hamish Kinnear, principal Middle East and North Africa analyst at risk intelligence company Verisk Maplecroft, noted that while the group already threatened shipping from prior positions, their capture of Mocha opens up the possibility of further advances towards the Bab el-Mandeb coastline and a tighter grip on the chokepoint.
The UN migration agency reported that the renewed hostilities and the lightning coastal offensive have displaced approximately 46,000 people, while sources on both sides estimate the fighting has killed more than 500 individuals.
Diplomatic Pressures and Washington’s Response
As Houthi forces closed in on the strait, Saudi Crown Prince Mohammed bin Salman placed at least two phone calls on Thursday to U.S. President Donald Trump, requesting U.S. military help to fight the group. Trump declined the request, indicating that the United States does not plan to expand its regional military campaign to include the Houthis.
“while empowering our regional partners to take the lead in managing and resolving regional security challenges.”
Senior administration official, via CNBC
The refusal leaves Riyadh and its regional allies largely on their own as they attempt to counter the mountain fighters.
Energy Markets and Supply Disruptions
The security crisis along the Red Sea corridor compounds months of disruption in the Strait of Hormuz, which has been effectively closed since U.S. and Israeli strikes on Iran began six months ago. With Hormuz handling about one-fifth of global oil and liquefied natural gas trade, Saudi Arabia had increasingly relied on its Red Sea route and the East-West oil pipeline to export crude.
Satellite imagery verified by Reuters showed smoke near the pipeline route on Thursday. Saudi state media reported that the pipeline was temporarily shut on Thursday following attacks that resulted in a number of injuries.
The International Energy Agency reported that Saudi crude supply fell by 2.3 million barrels per day in August down to 6 million bpd—the lowest level in over three decades—partly due to Houthi attacks on shipping. In the United States, average diesel prices topped $6 a gallon on Sept 11.
Counter-Offensive Plans and Ongoing Uncertainty
Yemeni government forces have indicated they are preparing a counter-offensive to retake lost ground along the western coastline. At the same time, Houthi military spokesperson Yahya Saree declared that maritime navigation remains safe for all shipping except Saudi vessels subject to an active blockade.
