U.S. oil prices slumped more than 2 percent to close at a five-week low on Thursday, as the dollar's rally on fears of Britain's exit from the EU hammered commodities priced in the currency.
The sixth straight day of declines marked the longest bear run for crude futures since January.
Also weighing on the oil complex was a lower-than-expected drawdown in U.S. crude inventories in spite of peak summer driving demand in the United States.
Brent crude fell $1.67, or 3.4 percent, at $47.29. The session low of $47.09 marked its lowest price since May 12, after touching an eight-month high of nearly $53 a barrel a week ago.
Front-month U.S. crude futures settled at $46.21 a barrel, down $1.80, or 3.8 percent.