Oil fell below $52 a barrel on Thursday, deepening losses over the previous four sessions as battered financial markets reflected ever lower confidence in the world economy and evidence mounted of falling fuel demand.
U.S. crude fell $1.42, to $52.20 a barrel by 7:09 a.m. EST, just off a session low of $51.95, the weakest level since January 2007.
London Brent crude shed $1.13 to $50.59 a barrel.
As economic slowdown has destroyed fuel demand, oil companies face the prospect of storing millions of barrels of unwanted oil.
Shipping brokers said on Thursday, U.S. oil trader Koch and Royal Dutch Shell had booked super tankers capable of storing eight million barrels of crude, only slightly less than a day's production from top exporter Saudi Arabia.
Oil has lost around two-thirds of its value since July's record above $147, in part because a global credit crunch has made investors pull their money out of riskier assets.
The falls on oil have mirrored weakness on equity markets, which dropped again on Thursday when European stocks hit their lowest level since March 2003.
Oil differs from other commodity markets in that producer group the Organization of the Petroleum exporting Countries can intervene to curb supplies, in theory providing support for prices.
Since early September, OPEC has said it will remove around 2 million barrels per day from international markets, but the market has taken the view falling demand is a bigger factor than tightening supply.
Deutsche Bank said on Wednesday oil could fall to as low as $40 a barrel next year.
Fears about their falling revenues have prompted some members of OPEC to urge further cuts as soon as possible and ministers are to gather for informal talks on November 29 in Cairo.
They will also meet again for a formal session on Dec. 17 in Algeria.
