Around 11,000 metric tons of Niger-origin soybeans bound for India were diverted to other Asian markets and sold at steep discounts as a widening customs probe into suspected import tax evasion deterred Indian buyers, four trade sources said on Thursday.

After being diverted at sea, the soybeans were sold to buyers in Vietnam, Indonesia and Bangladesh at prices between $470 and $510 per ton, compared with more than $650 per ton agreed by Indian buyers, who refused to take delivery after customs authorities stepped up scrutiny, the sources said.

Indian customs authorities are investigating a surge in soybean imports declared as originating in Niger, suspecting the cargoes came from Nigeria and were mislabelled to evade import tariffs, Reuters reported this month.

India allows duty-free imports from countries categorised as least-developed, such as Niger. India, the world's fifth-largest soybean producer, imported a record 1 million metric tons of soybeans this year after a poor harvest.

Authorities are seeking more documents to verify the soybeans' origin for duty-free entry, requiring importers to pay duties if they cannot prove the shipments originated in Niger.

Buyers are reluctant to take delivery because they fear the documents provided by sellers will not be sufficient to prove the soybeans' origin and they will be forced to pay the 45% duty, traders said. Indian customs authorities did not immediately respond to a request for comment.

Niger's Chamber of Commerce and Industry did not immediately respond to a request for comment. Around 60 containers of soybeans, or 1,500 tons, are still stranded at Jawaharlal Nehru Port (JNPT) near Mumbai after customs authorities stepped up scrutiny of imports declared as originating in Niger, following an internal alert issued to customs officials last month, as reported by Reuters.

Container freight rates have risen sharply in recent months due to the Iran war, and sellers are keen to avoid shipments getting stranded at ports, where they could incur hefty demurrage charges, the sources said.

India permits imports only of non-genetically modified (GM) soybeans, limiting supplies to a handful of African countries, including Benin, Nigeria, Togo and Niger, where non-GM beans command a steep premium over lab-altered varieties.

African sellers are diverting shipments to other Asian markets, where buyers typically purchase GM soybeans, forcing sellers to offer the non-GM beans at discounts to match GM soybean prices, said an official with an oil miller based in Ho Chi Minh City, Vietnam.

He and other trade officials declined to be named because they were not authorised to speak to the media under their companies’ policies.

Niger-origin soybeans were sold for as little as $470 per ton, compared with more than $650 agreed by Indian buyers, as sellers sought to limit losses rather than pay the import tax required for Indian customs clearance, the sources said.

India's soybean imports declared as originating in Niger rose to 404,429 tons in the first eight months of 2026 from zero, trade ministry data showed, even though Niger produces no significant quantity of the oilseed.