Oil prices have drifted below $55 a barrel amid worries over falling demand and slowing global growth, BBC reported.
US light, sweet crude was down to $54.40 by noon in Europe, after falling to $54.95 on Monday - the lowest level since January 2007.
Contracts for Brent North Sea crude dropped 48 cents to $51.83 a barrel.
Oil prices are down about 60% since their record highs of nearly $150 a barrel in July, with some Opec producers demanding cuts in production.
"The $55 level has gotten some support," said Victor Shum, energy analyst at consultancy Purvin & Gertz in Singapore.
"But downward pressure continues and we may approach $50 a barrel," he added.
Oil prices bounced back on Monday after surprisingly good US industrial output figures, but later fell amid more warnings of layoffs and reduced demand.
US industrial output rebounded in October after a sharp fall in September, the Federal Reserve said.
That helped ease some fears that demand for oil would be hurt as more countries slide into recession.
The Organisation of Petroleum Exporting Countries (Opec), which controls 40% of the world's oil supply, meets later this month to decide on the next course of action.
Iran is reportedly ready to call for a cut of between one million and 1.5 million barrels a day, on top of a 1.5 million barrel-a-day reduction last month.
However, Opec's president downplayed the chance of a November output cut.
"[Opec president] Chakib Khelil basically said that they will not cut on 29 November," said Dave Ernsberger, Asia director of global energy information provider Platts in Singapore.
Mr Khelil said Iran's call was a "wish".