West Texas Intermediate futures for September delivery climbed to $43.50 (+0.46%), while Brent crude advanced to $50.01 (+0.70%). The U.S. Energy Information Administration reported on Wednesday that the country's crude oil inventories fell 1.7 million barrels to 453.6 million barrels in the week ending August 7. The report also said U.S. oil production fell 70,000 barrels a day to about 9.4 million barrels.

The EIA expects global oil demand growth in 2015 to be the strongest in five years, although it added that global oversupply would last through 2016. However many analysts doubt such optimistic forecasts considering weakness of China's economy.