Tanker diversions from Bab el-Mandeb expose the Red Sea route used to bypass disruption in Hormuz, raising oil, freight and insurance risksCommercial tankers have begun changing course away from the Bab el-Mandeb Strait, Brent crude has risen above $94 a barrel and Asian refiners are examining journeys that could add as much as four weeks to deliveries after Yemen’s Houthi movement threatened ships using Saudi Arabian ports.
Four tankers changed course in the Red Sea on Wednesday, following three diversions the previous day, while a Chinese vehicle carrier abandoned a route towards Jeddah, according to shipping data reviewed by Reuters. Some vessels turned north towards the Suez Canal; others paused while operators assessed the threat.
The disruption has transformed a confrontation centred on the Strait of Hormuz into a potential two-chokepoint crisis. Brent crude rose 3.6 per cent to $94.31 a barrel, Reuters reported, as traders assessed whether pressure on Bab el-Mandeb could restrict the Red Sea route increasingly used to bypass disruption in the Gulf.
Saudi Arabia has shipped an average of more than 4.5mn barrels a day of crude and refined products from its Red Sea terminal at Yanbu since April, with about 70 per cent destined for Asia, according to Reuters and shipping data providers. Energy Aspects estimates that more than 3mn barrels a day of Saudi crude could be forced on to longer routes if Bab el-Mandeb became inaccessible.
The immediate trigger for renewed Houthi-Saudi hostilities was a July 13 strike on Sana’a International Airport claimed by Yemen’s internationally recognised government. The wider maritime escalation unfolded as the US-Iran ceasefire collapsed and Tehran sought additional leverage against renewed American military operations.
Available evidence does not indicate that Saudi forces directly conducted the airport strike. Nor does it support treating the Houthis solely as instruments of Iran. The movement has its own domestic objectives and long standing confrontation with Riyadh, although the timing and scope of its maritime threat also appear to advance Tehran’s interest in placing pressure on two of the world’s most important energy routes.
Yemen’s internationally recognised government said it struck the runway at Sana’a airport to prevent an Iranian aircraft from landing without authorisation, describing the flight as a violation of Yemeni sovereignty.
The aircraft subsequently landed at Hodeidah, another airport controlled by the Houthis. The nature of its cargo and full passenger manifest were not independently established. The Houthis said it was carrying a delegation returning from Iran.
The Aden-based government supplied a stated security justification for the operation. But no independently verified evidence has shown that the aircraft carried weapons or posed an immediate military threat requiring the runway of a civilian airport to be attacked.
The Houthis blamed Saudi Arabia for backing the internationally recognised government, although no evidence has emerged that Saudi forces directly conducted the runway strike.
Within hours, the movement launched missiles towards Abha International Airport in southern Saudi Arabia. The Saudi-led coalition said they were intercepted. It was the first claimed Houthi attack on Saudi territory since an informal truce began in 2022.
Houthi leader Abdul-Malik al-Houthi subsequently warned that Saudi airports, ports, oil installations and other strategic facilities could be targeted if Riyadh escalated further.
The movement then widened its declared target set. In a notice sent to shipping companies on July 20, its maritime coordination centre warned vessels against loading or discharging cargo at Saudi ports and described the measure as a naval blockade.
The declaration does not amount to an internationally recognised blockade, and the Houthis have not physically closed Bab el-Mandeb. But commercial diversions demonstrate that shipowners, charterers and refiners regard the threat as operationally credible.
“Changing behaviour by tankers tells us that they are taking the threats seriously,” said Matt Smith, commodity research director at Kpler. Saudi crude and product movements through Bab el-Mandeb exceeded 4mn barrels a day last month, according to Kpler data.
The escalation followed the breakdown of a ceasefire memorandum reported by Reuters as having been negotiated in Islamabad between Washington and Tehran in June.
The agreement suspended hostilities, reopened Hormuz to commercial traffic for 60 days and envisaged temporary waivers for Iranian oil exports and procedures for releasing frozen Iranian funds.
Iran interpreted the maritime clause as recognition of its right to manage traffic through the entire strait. The United States and Gulf governments understood it as an obligation for Tehran to guarantee unrestricted passage without tolls or coercive controls.
Washington accused Iran of attacking vessels using routes Tehran had not approved. Iran accused the US of failing to deliver sanctions relief and unrestricted access to frozen assets.
On July 7, Washington revoked the licence permitting Iranian oil sales, saying Iranian actions in Hormuz were unacceptable. Tehran described the decision as a breach of the memorandum. President Donald Trump subsequently declared the agreement over and US forces resumed sustained attacks.
It is therefore inaccurate to describe the collapse as a single, undisputed American decision to break functioning peace talks.
The memorandum had already entered crisis because of contested maritime incidents, incompatible interpretations and disagreement over economic concessions. Washington nevertheless took the decisive formal steps that ended its practical implementation: revoking the oil waiver, resuming broad military operations and declaring the ceasefire over.
