China became the biggest buyer of US crude oil in February, surpassing Canada, at a time when Opec is cutting back output.

China imported 8.08 million barrels of US light crude, nearly quadrupling its January purchases, according to data released by the US Census Bureau. That helped boost US exports to a record 31.2 million barrels during the month. Canada, the US’s largest trade partner, imported 6.84 million, down 20 per cent from a month earlier. The surge in US shipments to Asia, a market long dominated by Saudi Arabia and other Middle East producers, comes as the Organization of Petroleum Exporting Countries trims output in an effort to end a glut that battered the economies of global energy exporters. Saudi Arabia reduced its pricing for some of its April crude sales to Asia as supplies from the US became more competitive.

"The US is a larger exporter of crude than many Opec countries," John Auers, executive vice president at energy consultant Turner Mason & Co. in Dallas, said by phone. "That China is buying more means that the US has become a larger player in the global crude export market."

Ships hauling US crude to Asia included the supertanker Alex, which headed for Ningbo in eastern China after loading 2 million barrels of West Texas Intermediate crude in the Gulf of Mexico in late February, a person familiar with the matter said last month.