Oil prices set a new record above $50 a barrel yesterday as a prolonged US production outage following Hurricane Ivan attracted fresh speculative buying.
US light crude rose 58 cents to $50.49 a barrel, beating by two cents last week's all-time record. London Brent crude rose 60 cents to $46.79 a barrel.
Supply anxiety is building ahead of the northern hemisphere winter, when demand for heating oil surges. Inventories of crude and distillates in the world's top energy user, the United States, are running up to 4 percent below last year.
"US production has been slow to recover from Hurricane Ivan and people are worried by the low level crude and distillate inventories ahead of winter," said Tetsu Emori, chief commodities strategist at Mitsui Bussan Futures in Tokyo.
"People are still watching Nigeria and Iraq. With Opec producing almost at full capacity, any stoppage in Iraq's or Nigeria's exports would upset the supply-demand balance. It's a very dangerous situation."
In the US Gulf of Mexico, nearly 29 per cent, or about 480,000 barrels per day (bpd), of oil output remained shut, three weeks after Hurricane Ivan first hit the region, the US Minerals Management Service said on Monday.
Dealers will now look to US oil inventory data, due out today, to gauge how comfortable oil supplies are in the weeks ahead of winter.
A Reuters poll of eight analysts predicted on average a fall in distillate stocks - including heating oil, the main winter fuel in the northeast of the country - by 800,000 barrels and a drop in gasoline stocks by 600,000 barrels.
The weekly report by the Energy Information Administration due was expected to show crude stocks rising in the week to October 1 by 1.1 million barrels from the week earlier.
Oil prices had eased on Monday after Nigerian rebels withdrew a threat to target the country's over 2.3 million bpd of oil production facilities, but concerns lingered over the Opec member's stability in the near term.
Iraq also remains volatile, with saboteurs regularly attacking pipelines. On Monday an internal line linking the country's north and south fields was hit, although this did not affect exports.
Together the two countries produce over 4.5 million bpd - more than twice the amount of spare production capacity held by members of the Organisation of the Petroleum Exporting Countries, most of that in Saudi Arabia.
Opec President Purnomo Yusgiantoro said yesterday he expected oil prices to fall in the first part of next year if supply fears in the Middle East - and particularly the disruptive turmoil in Iraq - were to fade.
But market bulls are encouraged by signs that speculative funds, a major factor in this year's steep oil price rally, continue to buy into the market, despite the highest prices on record.
Speculators on crude oil on the New York Mercantile Exchange increased net long positions in the week ended September 28 in a bet prices would rise, the US Commodity Futures Trading Commission said.