Oil prices tumbled on Thursday as the United States announced a sharp increase in its energy stockpiles, traders said.
New York's main futures contract, light sweet crude for delivery in March, slumped USD 2.52 to USD 41.02 a barrel.
Brent North Sea crude for March shed USD 1.14 to USD 43.91 on London's InterContinental Exchange.
"We had a big build again in the crude" inventories, said Sucden broker Robert Montefusco, explaining the plunge in prices.
Crude inventories soared by 6.1 million barrels last week in leading energy consuming nation the United States, the Department of Energy announced.
The US government released its latest weekly energy report a day later than usual because of Monday's public holiday.
Oil has plummeted from record highs above 147 dollars in July because of a worsening global economic slowdown that has dented demand.
Hopes of a pick-up in demand were not helped Thursday as it was revealed that unemployment claims had hit a 26-year high and housing construction fallen to half-century lows in the United States, the world's biggest energy consumer.
"The labor market remains a disaster," said Ian Shepherdson, chief US economist at High Frequency Economics.