Oil prices fell for a second consecutive day on Thursday after U.S. President Donald Trump signed into law a bill backing protesters in Hong Kong, fuelling tensions with China.
Brent crude was down 64 cents, or 1%, at $63.42 a barrel by 1609 GMT, Reuters said.
West Texas Intermediate crude fell 31 cents, or 0.5%, to $57.80, with many U.S. traders away for the Thanksgiving holiday.
China warned the United States that it would take "firm countermeasures" in response to U.S. legislation backing anti-government protesters in Hong Kong.
Investors are concerned that the move might delay further a preliminary agreement between the United States and China to put an end to their trade war that has slowed global economic growth, and consequently consumption of oil.
Prices extended losses from Wednesday when government data showed U.S. crude inventories swelled by 1.6 million barrels last week as production rose to a record 12.9 million barrels per day (bpd) and refinery runs slowed.
Investors have also been focused on next week's meeting of the Organization of the Petroleum Exporting Countries and allies including Russia, a group known as OPEC+, which have been withholding production to support prices.