Oil dipped today as a stronger US dollar and progress in controlling wildfires in Canada's crude-producing Alberta province dampened prices.
US benchmark West Texas Intermediate for July delivery was down 20 cents at $47.88.
Brent North Sea oil, the European benchmark, for July delivery slid 29 cents at $48.06.
Remarks by US Federal Reserve officials hinting at a June interest rate hike also pushed up the greenback against major currencies, pushing oil lower.
A stronger greenback weighs down oil prices, as it curtails demand by making the dollar-priced commodity more expensive.
Prices have rebounded since plunging to near 13-year lows below $30 in February but are still well short of peaks of more than $100 a barrel reached in June 2014.
There are market concerns that a supply glut may return following news of Canada lifting evacuation orders for several oil production sites in fire-ravaged Alberta province amid cooler weather and light rain.
Prices were also weakened this week by comments from Iranian officials who vowed to keep up oil production after the lifting of Western sanctions in January.
All eyes are now on the OPEC meeting in Vienna on June 2 where it is hoped an agreement to cut production can be reached.
The market is also keeping an eye out for inventory data from the American Petroleum Institute, which is due later today, followed by US Energy Information Administration figures tomorrow.