Chinese buyers have cancelled as much as 150,000 tonnes of soyoil cargoes from South America as ample supplies have pushed domestic prices of the edible oil lower than the cost of imports, said an official think-tank on Wednesday.

The soyoil orders were cancelled by Chinese buyers because weakening domestic soyoil prices: made the imports too expensive, said the China National Grain and Oils Information Centre.

China imports soyoil mainly from Argentina, the world's largest exporter. China's imports January to April fell 44 percent from a year ago to 220,024 tonnes, according to official customs data.

Expectation of huge imports of soy by top soy buyer China have weakened domestic prices of the product. The most-traded Dalian September soyoil contract hovered near more than four-year lows for domestic soyoil futures, trading just above 7,500 yuan ($1,200) per tonne on Wednesday.

South American soyoil cargoes for June delivery were quoted at 8,150 yuan per tonne after import tax.

The centre expected soy imports in May at 5.6 million tonnes while imports in June could jump to record 7 million tonnes.