Oil prices gained on Thursday after government data showed U.S. oil inventory declined last week.

The Energy Information Administration (EIA) said in its weekly report on Wednesday that crude inventories fell by 8.95 million barrels in the August 11 week, nearly three times analysts' expectations for a decrease of 3.1 million barrels. Meanwhile, data showed gasoline and distillate inventories rose mildly.

Analyst said report eased market concerns for a global oversupply and supported the oil prices on Thursday.

The West Texas Intermediate for September Delivery added 0.31 dollar to settle at 47.09 dollars a barrel on the New York Mercantile Exchange, while Brent crude for October delivery gained 0.76 dollar to close at 51.03 dollars a barrel on the London ICE Futures Exchange.