LONDON (AFP) - World oil prices ducked back below 48 dollars a barrel amid speculation that US government may tap strategic reserves as inventories plunge due to Hurricane Ivan, analysts said.
New York's main contract, light sweet crude for delivery in November, eased 42 cents to 47.93 dollars a barrel in pre-opening electronic trading.
The contract surged 1.59 dollars to 48.35 dollars a barrel on Wednesday, approaching a record close on August 19 of 48.70 dollars and an all-time high of 49.40 dollars seen on August 20.
Benchmark Brent North Sea crude oil for delivery in November dropped 27 cents to 44.66 dollars a barrel in early deals in London.
Markets cooled amid speculation that the United States might release some crude oil from its strategic petroleum reserves (SPR), said Commerzbank analyst David Thomas.
"They did it back in 2002 when there were extraordinary circumstances and security of supply was at risk, so they have done it historically and they might do it again."
The White House has pledged to fill the reserve to its capacity of 700 million barrels. The reserves are kept in salt mines on the Gulf Coast in Louisiana and Texas.
"A couple of refiners have apparently made a request to the government to borrow from the SPR, because their stocks and tankers are too low. It would be a question of borrowing it and giving it back as soon as supplies arrive towards their storage centre," said Thomas.
"But obviously the market would take it nervously because it would be seen as a release of strategic reserves rather than just a borrowing."
Prices surged on Wednesday on news that US oil inventories tumbled to their lowest levels since February last week in the wake of Hurricane Ivan.
The US Department of Energy said crude reserves fell by 9.1 million barrels in the week to September 17 to 269.5 million barrels, the lowest levels since February 6.
The American Petroleum Institute, a private trade association, said its survey showed an even steeper drop of 12.9 million barrels to 266.7 million.
"This was one of the largest week-on-week draws in history," said US-based analyst Jason Schenker at Wachovia Securities.