Oil prices fell as much as 4 percent on Friday, dragged down by uncertainty over whether the Organization of the Petroleum Exporting Countries will reach an output deal.
Futures extended early losses after Saudi Arabia said it will not attend talks on Monday with non-OPEC producers to discuss supply cuts.
Brent crude oil futures were trading at $47.02, down $1.98, or 4 percent, by 1:35 p.m. ET (1835 GMT). U.S. West Texas Intermediate (WTI) crude futures settled down $1.90, or 4 percent, at $46.06 per barrel.
Overall activity was thin after the U.S. Thanksgiving holiday and ahead of the weekend.