Oil prices fell on Thursday, extending losses that began in the previous session, amid signs of rising supplies from the United States and concerns about declining energy demand from Asia.
Brent crude futures fell 28 cents to $80.90 a barrel by 0001 GMT, while US West Texas Intermediate crude fell 31 cents to $76.35 a barrel.
The two benchmarks fell by more than 1.5 percent in the previous session.
US crude inventories rose by 3.6 million barrels last week to 421.9 million barrels, according to the US Energy Information Administration, far exceeding analysts' expectations in a Reuters poll for an increase of 1.8 million barrels.
US crude production stabilized at a record level of 13.2 million barrels per day.
In Asia, oil refinery production in China declined in October from high levels recorded the previous month.
