Brent extended losses from a four-year low as Saudi Arabia offered customers in Asia record discounts on its crude, bolstering speculation it's defending market share. West Texas Intermediate dropped in New York.

Futures fell as much as 0.7 percent in London and are headed for a second weekly decline. State-run Saudi Arabian Oil Co. cut its differential for Arab Light sales to Asia next month to $2 a barrel below a regional benchmark, according to a company statement. That's the lowest in at least 14 years. The kingdom doesn't want to subsidize Iran, Iraq and Venezuela and is willing to let the market decide prices, said Daniel Yergin, an energy analyst and Pulitzer Prize-winning author.

Crude slumped 18 percent last month as the Organization of Petroleum Exporting Countries maintained its output quota, letting prices decrease to a level that may slow U.S. production. Saudi Arabia has no price target and will let the market decide at what level oil should trade for now, said a person familiar with its policy.

“It seems what the Saudis want, the Saudis are going to get,” Phil Flynn, a senior market analyst at Price Futures Group in Chicago, said by e-mail today. “We're going to see prices continue to be under pressure. It is still game on.”

Brent for January settlement slid as much as 50 cents to $69.14 a barrel on the London-based ICE Futures Europe exchange and was at $69.18 at 1 p.m. Singapore time. The contract lost 28 cents to $69.64 yesterday, the lowest close since May 2010. The European benchmark crude traded at a premium of $2.81 to WTI, compared with $4 on Nov. 28. Prices, down 1.4 percent this week, have dropped 38 percent this year.