It was the second week in a row the U.S. Energy Information Administration reported a sharp and unexpected drop in oil inventories.

"The decline in U.S. crude oil inventories has been a key driver of oil prices," said David Moore, commodity strategist at the Commonwealth Bank of Australia in Sydney.

Light, sweet crude for December delivery rose as high as US$96.24 a barrel in electronic trading on the New York Mercantile Exchange by midafternoon in Singapore before dropping to US$95.59 a barrel.

Crude prices have reached inflation-adjusted highs set in early 1980. Depending on the how the adjustment is calculated, US$38 a barrel then would be worth US$96 to US$101 or more today.

"We are stepping into an unknown area. Nobody wants to sell (given the fear of a) further rise," broker Ken Hasegawa of Fimat Japan told Dow Jones Newswires.

The December Nymex crude contract rose US$4.15 Wednesday to US$94.53 a barrel - the highest-ever settlement.

December Brent crude futures also surged to a new trading record of US$91.63 a barrel Thursday on the ICE futures exchange in London, up US$1 from the previous session, before retreating to US$91.37.

In its weekly inventory report, the U.S. Energy Department's Energy Information Administration said oil supplies fell by 3.9 million barrels last week. Analysts surveyed by Dow Jones Newswires, on average, had expected an increase of 100,000 barrels.

"The report acted to solidify concerns about the possibility of tightening market conditions ahead of the northern winter," Moore said.

Much of that decline was due to a big drop in crude supplies at a closely watched oil terminal in Cushing, Oklahoma.

Cushing supplies have been under pressure in recent months due to differences in the price between front-month oil contracts and those for delivery in future months. This price difference, or spread, has given storage tank owners a financial incentive to sell their oil, rather than hold it in inventory. Analysts have also blamed falling Cushing supplies, in part, for the rally in which oil prices have jumped 35 percent since August. Pravda.ru