West Texas Intermediate futures for October delivery climbed to $44.89 (+0.67%), while Brent crude is currently at $47.85 (+0.21%). Both crudes advanced, but gains are likely to be limited as investors await the result of the Federal Reserve's meeting.

An increase in U.S. interest rates will boost the greenback but would likely weigh oil prices by making crude more expensive for foreign importers using other currencies.

Yesterday the American Petroleum Institute reported a 3.1-million-barrel decline in U.S. commercial oil inventories last week, a positive factor for oil prices. The U.S. Energy Information Administration will release its closely-watched data later today. Pricing agency Platts expects U.S. crude oil stocks to fall by 200,000 barrels.