Crude futures slid after a meeting between nations supplying a third of the world's oil failed to result in a pledge to curb output in the run-up to this week's OPEC meeting.

Venezuela, Saudi Arabia, Mexico and Russia said they plan to start quarterly monitoring of oil prices. Today's talks in Vienna didn't result in any joint commitment to reduce supplies, said Igor Sechin, who runs Russian state oil producer OAO Rosneft.

"Even those four countries are not agreeing to any kind of cut, and the last thing the Saudis want is to be the ones doing all the cutting," said Tariq Zahir, a New York-based commodity fund manager at Tyche Capital Advisors. "You have to get an above 2-million-barrel cut from OPEC to stabilize the market."

Brent for January settlement lost $1.26, or 1.6 percent, to $78.42 a barrel at 12:08 p.m. New York time on the London-based ICE Futures Europe exchange. The volume of all futures was 5.2 percent above the 100-day average.

WTI for January delivery fell $1.38, or 1.8 percent, to $74.40 a barrel on the New York Mercantile Exchange. Volume was 21 percent below the 100-day average. Brent's premium to WTI was $4.04 on the ICE.