UNIPEC, the trading arm of China’s oil major Sinopec, has suspended crude oil imports from the United States due to a growing trade spat between China and the United States, three sources familiar with the situation said Friday.

It is not clear how long the temporary halt will last, but one of the sources said Unipec has no new bookings of U.S. crude until at least October.

Unipec and Sinopec, Asia’s largest refiner and biggest buyer of U.S. oil, did not respond to requests for comment.

Chinese buyers had already slowed their purchases of U.S. oil to avoid a likely import tariff amid the escalating trade dispute between the world’s two largest economies.

China has put U.S. energy products, including crude oil and refined products, on a list of goods it will hit with a 25 percent import tax in retaliation for similar moves by the United States. It has not said when it will impose the tariffs.

Unipec said earlier this year it expects to trade up to 300,000 barrels per day (bpd) of U.S. crude oil by the end of the year, about triple its trading volume of U.S. oil last year.

China’s crude oil imports from the United States reached an average of 334,880 bpd in the first eight months of this year, according to trade flows data on Thomson Reuters Eikon.

The amount of U.S. crude arriving in September is expect to fall to 197,515 bpd, as only three supertankers are en route to China, the data showed.

China is the largest buyer of U.S. crude after Canada.

(SD-Agencies)