China exported not a single drop of crude oil to North Korea in the first nine months this year, according to formal data.
If true, it might reflect widespread speculation that the relations between the communist allies have been strained to some extent due to Pyongyang's repeated provocative acts.
South Korean officials, however, believe China is continuing to send crude oil to North Korea either in hidden trade or in the form of aid.
"Without China's provision of crude oil, the operation of many of North Korea's industrial facilities and vehicles would be suspended. But there has been no such indication yet," an intelligence official said.
Beijing may be deliberately excluding its crude oil shipments to Pyongyang from the customs data in a bid to give the world the impression that it is joining the international community's efforts to put pressure on it, another government official said.
He dismissed the view that the North has replaced China with Russia as its main source of crude oil imports.
"North Korea has brought in more crude oil from Russia this year, but the total amount is still less than 100,000 tons," he said.
North Korea used to import an annual average of half a million tons of crude oil from China. (Yonhap)