Crude prices wavered on Monday on light trading due to holidays in the markets, while the dollar kept trading near eight-week highs.
U.S. crude futures last traded at $49.34 a barrel, compared to the opening of $49.52, with a session-high at $49.69, and a low at $49.05, after prices hit a seven-month peak last week at $50.18.
Crude's dithering comes as investors favor more gains due to renewed confidence in the oil markets, but the dollar's recent rise stems the potential rise of the commodity.
Trading is light in the markets to to holiday as investors take their day off, while the dollar hold its gains, pressuring crude prices lower.
The dollar index, which gauges the greenback's performance against a basket of six major rivals, last traded at 95.71, down from the opening of 95.83, with a session-low at 95.66, and an eight-week peak at 95.96, after the index registered its fourth consecutive weekly profit.