US benchmark West Texas Intermediate for May delivery was down 65 cents at $45.92 and Brent tumbled 58 cents to $54.74.
Daniel Ang, an investment analyst with Phillip Futures in Singapore, said it was “the same fundamental issue of supply and demand” affecting the market.
“Oil prices are falling because of the bearish sentiment that people have towards oil right now,” he told AFP.
Prices have collapsed by about 60 percent since June as global supplies of the commodity, boosted by strong production in the United States and the OPEC cartel, outpace demand.
Bloomberg News quoted Saudi Arabia’s oil minister Ali al- Naimi as saying on Sunday that his country is producing almost 10 million barrels of crude a day.
Saudi Arabia, the main producer in the Organization of the Petroleum Exporting Countries, pumped 9.85 million barrels a day in February, according to Bloomberg.