Houthis declared a maritime blockade against Saudi Arabia earlier last week. File Image / Pixabay

Global bunker supplier and trading firm Peninsula has warned that renewed Red Sea diversions could tighten bunker fuel supply as ships take longer routes around the Cape of Good Hope.

The longer voyages and stricter sulfur emissions rules are increasing bunker fuel demand and operating costs for shipowners, the firm said in an emailed statement on Friday.

Yemen's Houthi movement has resumed attacks on commercial shipping in the Red Sea after announcing a maritime blockade on Saudi Arabia last week.

Some container lines had recently resumed Suez Canal transits after Houthi attacks eased earlier this year. However, the latest escalation could once again force ships to avoid the Red Sea and Suez Canal, instead taking the longer route around the Cape of Good Hope.

"The industry could be dealing with a sudden, significant increase in fuel consumption," Kenny MacLean, Chief Operations Officer at Peninsula, said.

"This is more complex than simply plotting a longer course – it will require a fundamental recalibration of voyage economics that will squeeze global bunker supply at a time when demand already outstrips supply."

Peninsula estimates a typical Suezmax tanker taking the diverted route would require about 1,500 mt of additional bunker fuel, adding around $800,000 in bunker costs and producing roughly 3,800 mt of extra CO2 emissions.

The company said spot rates for Suezmax tankers are already rising as charterers seek available tonnage.

The supplier also warned that ships transiting the Mediterranean must comply with MedECA rules by switching from standard VLSFO to 0.1% sulfur fuel, such as LSMGO or suitable biofuels, or risk fines and detention.

"Operators are navigating a regulatory and logistical minefield," Richard Alvarez, global head of sales at Peninsula, said. "

Peninsula expects bunker demand to rise at alternative supply hubs including Port Said, Malta, Gibraltar, Algeciras, Las Palmas, Algoa Bay and Port Louis.

The company ranked second in Ship & Bunker’s Top 10 Bunker Companies list for 2026.