In late July, two tankers carrying Saudi crude for Asian buyers departed the Red Sea port of Yanbu, heading south toward the Bab al-Mandeb strait. Within hours, they reversed course. The Rodos and the Xin Long Yang, together hauling 2.8 million barrels, turned back after Yemen's Houthi movement announced a blockade of Saudi ports. The detour was brief, but it laid bare a deeper vulnerability: Asia's workaround for a closed Strait of Hormuz is now itself under fire.
For six months, the region's answer to the near-total shutdown of Hormuz—triggered by the US-Israeli war on Iran—has been to reroute. Saudi Arabia pipes crude across the desert to the Red Sea, where tankers carry it onward. That bypass, however, has become a target. Analysts estimate that roughly 6 million barrels a day destined for Asia transit Bab al-Mandeb, and that flow is now at risk.
A bypass under attack
The threat turned real in September. Houthi forces consolidated control over Yemen's Red Sea coastline, and strikes shut down Saudi Arabia's East-West pipeline. On September 19, firefighters battled a blaze at an Aramco fuel depot near Riyadh's airport as the Houthis claimed attacks on Yanbu itself. The exposure of Asia's largest buyers is stark: Saudi crude accounted for 34.1% of South Korea's imports in July, 27.3% of Japan's, 14.9% of China's, and 10.2% of India's. Yanbu had taken over the majority of Saudi exports that once left through the Gulf.
The Houthis do not need to sink ships to control the waterway. Bab al-Mandeb is only about 30 kilometers wide at its narrowest point, and the mere threat of attack can drive insurers and shipowners to seek alternative routes. Iran gains leverage cheaply: it keeps its distance while the Houthis impose the costs. Reuters reported in July that the Houthis were considering fees on ships transiting the strait, with Iranian advisers reportedly helping to set up a regulating authority. The group denied the plan, but Yemen's foreign minister-designate said it was seeking to copy the Iranian model—a reference to Tehran's own efforts to charge ships passing through Hormuz. Whether tolls materialize or not, the direction is clear: control of a chokepoint is becoming something that can be monetized as well as weaponized.
The alternative route is logistically punishing. Sending Saudi crude to Asia around Africa would add roughly 10,000 nautical miles. Costs are compounding: Physical Dated Brent stood at $125.42 a barrel on September 18, and tanker charter rates have reportedly topped $1 million a day. Analysts estimate that the twin closure adds millions of dollars to a single voyage once diversions, war-risk insurance, and delays are counted.
Asia's thinning buffers
The Red Sea–Suez corridor normally carries around 15% of global maritime trade by volume. When it closes, ships take the Cape of Good Hope, adding at least 10 days. This was never a purely regional problem. Attacks had largely subsided after a 2025 ceasefire, but traffic barely recovered before the Iran war renewed the fear. UNCTAD warned in April that the Hormuz shock was feeding through trade, prices, and finance, leaving developing economies with weaker currencies and higher borrowing costs.
Four countries—China, India, Japan, and South Korea—accounted for 75% of oil and 59% of LNG flows through Hormuz before the war. But their vulnerability differs. Imported fossil fuels supply 87% of Japan's energy and 81% of South Korea's, against 20% for China and 35% for India. East Asia has buffers, but they are thinning fast. China holds large crude stockpiles, yet crude inventories elsewhere in Asia have already fallen 13%, and gas is harder to store. Japan, South Korea, and Taiwan import more than 95% of their natural gas. Southeast Asia sources roughly half its crude from the Middle East, and reserves are built for short disruptions—running dangerously thin as the conflict enters its seventh month.
Asia's early response shows the weakness. In the first week of the war, Thailand suspended fuel exports, while China ordered its largest refineries to halt diesel and petrol exports. Governments protected their own supply, which is understandable, leaving neighbors competing for what remained. A region that has long depended on the same waterways for its energy security is now mutually vulnerable as they close.
Pakistan feels the pinch
Pakistan shows how fast the shock reaches households. A large share of its oil comes from Saudi Arabia. With Hormuz closed, its alternative route through the Red Sea has also been disrupted. By September 20, petrol stood at 389.14 rupees a liter and diesel at 424 rupees, up 68 and 57 rupees respectively since July 22. A Pakistani petroleum official said that with Hormuz closed, Bab al-Mandeb is the only route currently available for importing petroleum products. Losing it would push Islamabad toward suppliers as far away as Nigeria and the United States, raising freight costs. The government has introduced a relief scheme worth about $270 million for motorcycle and small-car users, after petrol rose 24% and diesel 28% since July 1.
Pakistan's exposure is also strategic. Its defense pact with Saudi Arabia and Turkey has drawn a direct Houthi warning against intervening in Yemen. The country that needs the Red Sea route open is also a country the group that threatens it has singled out.
What Asia can do
The region cannot wait for someone else to secure its supply. Washington has declined direct strikes on the Houthis, though it is providing intelligence and targeting help. Even Washington's choices about Iran turn on Gulf energy: Trump held off major attacks in August after Saudi Arabia and Qatar warned Iran could retaliate against Saudi oil and gas infrastructure. The same pipelines Asia relies on now shape Washington's war decision-making.
Three steps could help. First, importers should treat every bypass as a chokepoint in its own right. A single point of failure—whether Hormuz or Bab al-Mandeb—should be a red flag for diversification. Second, strategic reserves need to be larger and more flexible, especially for gas, which is harder to store. Third, regional cooperation on emergency sharing could mitigate the worst effects of a prolonged closure. Japan has already begun taking charge of its energy security, but the broader region needs a coordinated response.
The pipeline attack and the surge in US energy costs underscore the global stakes. Asia's energy security is no longer just a matter of market access; it is a strategic vulnerability that the Houthis and Iran have learned to exploit. The region's governments must act now, before the next chokepoint closes.
