(Bloomberg) -- A flotilla of supertankers laden with Venezuelan fuel oil is threatening to shake up Asian energy markets, less than two months after the US eased sanctions on the South American nation.

Three Very Large Crude Carriers — capable of hauling up to 2 million barrels each — offloaded cargoes of the sludgy and sulfurous oil product in Southeast Asia in November, according to fixtures and Bloomberg ship-tracking data.

China’s independent refiners have been the main buyers of Venezuelan crude and fuel oil since Washington implemented sanctions in 2019, but the relaxation of the restrictions is now spurring wider interest, particularly from India. The fuel oil — used to power ships — is refined in Venezuela, but is commonly processed into bitumen in Asia or used as feedstock to make low quality diesel.

The increased flows coincide with Beijing awarding Chinese processors more fuel oil import quotas for this year. There’s also been a surge in trading of high-sulfur fuel oil this month in a window run by S&P Global Commodity Insights, where Trafigura Group has been the biggest seller and PetroChina Co. the largest buyer.

The volumes arriving in Asia are still relatively small, said Serena Huang, lead Asia analyst at Vortexa Ltd. “So it’s not likely to move the needle much in terms of regional fuel oil prices.”   

Still, as Venezuela ramps up its crude production, price-sensitive buyers in India and China — which lapped up Russian crude in the early days of its invasion of Ukraine — may pick up more barrels from the South American producer as long as the price stays low, traders said.

Much of the Venezuelan fuel oil being discharged in Southeast Asia will eventually find its way to China, said Ivan Mathews, head of Asian refining and global fuel oil at FGE.

Read More: Indian State Refiners May Sharpen Competition for Venezuelan Oil

As well as potentially affecting fuel markets, the influx of Venezuelan fuel oil may pose safety risks, given it’s being transported on older tankers and is often transferred to other vessels at sea. The three VLCCs — Big Star, Loggam and Glory Forever — are all at least 19 years old and discharged their cargoes in the busy waters where Singapore, Malaysia and Indonesia meet. 

All three loaded in Venezuela in July and August, before the US relaxed its sanctions, according to Kpler, which may be a reason for the ship-to-ship transfers. Another smaller Suezmax tanker, the 23-year-old Cameroon-flagged Liberty, laden with Venezuelan fuel oil had its cargo removed after being grounded near Singapore since Dec. 3.

©2023 Bloomberg L.P.