Oil prices have tumbled below $US50, as plunging equities and weak US data sparked fresh concern that a worldwide recession could ravage energy demand, traders said.
In New York, light sweet crude for delivery in December dived to $US49.75 a barrel on Thursday - the lowest level since May 2005. The December contract expires at the close.
Brent North Sea crude for January tumbled to $US48.20, which was also last seen in May 2005. Brent closed on Wednesday at $US51.72.
Crude futures were pulled down by fears about the impact of the ongoing chronic global financial crisis, analysts said.
Oil prices have now plunged by about two-thirds since striking record highs above $US147 in July as a global economic slowdown slashes worldwide demand for energy.
"The oil market is reacting to yet more negative news on the prospects for the global economy," said IHS Global Insight oil analyst Simon Wardell.
"With stock markets continuing to fall around the world, and particularly in Asia, there is just no positive news out there which could help restore confidence in oil markets."
Stock markets plunged on Thursday as a jump in US jobless figures and fresh job cuts worldwide deepened fears of recession and sent investors fleeing for cover.
The latest economic news remained grim as the US Labor Department said new claims for unemployment benefits jumped to a 16-year high of 542,000.
Later Thursday, oil prices went on to recover somewhat, with New York oil at $US50.56 and Brent at $US49.05 in late afternoon London trade.
Wardell said that "the market is still searching for a floor and until there some stronger signs that supply is being cut, we are likely to see continued price weakness".
