Crude oil prices careened lower on news of surging US energy reserves that highlighted falling demand in a cooling global economy gripped in a credit squeeze.
A sharp rise in the dollar also put pressure on the dollar-priced commodity, making it more expensive for buyers using relatively weaker currencies.
In London, Brent North Sea crude for December delivery fell to $64.59, its lowest level since May 9, 2007.
US crude slid to $66.73 a barrel, a low last seen on June 14, 2007.
The US Department of Energy has revealed that US crude oil reserves jumped 3.2 million barrels to 311.4 million barrels in the week ending October 17. That beat market expectations for a smaller increase.
Gasoline or petrol inventories rose by 2.7 million barrels last week, the DoE added.
