* OPEC cuts 2.2 million bpd of crude output
* Dealers say record cut not enough to offset demand slide (Updates prices)
By Richard Valdmanis
NEW YORK, Dec 17 (Reuters) - Oil prices dropped 8 percent to their lowest in more than four years on Wednesday after OPEC announced a record supply cut that dealers said may fail to offset slumping world energy demand.
U.S. crude oil prices <CLc1> fell $3.61 to $39.99 a barrel by 2:30 p.m. EST (1930 GMT), the first time below $40 since July 2004. London Brent <LCOc1> fell $1.20 to $45.45.
Oil prices have fallen more than $100 since July as a global financial crisis cuts into consumer and industrial fuel demand, and top forecasters are now predicting the first decline in world energy use since 1983.
The Organization of the Petroleum Exporting Countries, eager to push prices back up, announced on Wednesday an agreement to cut 2.2 million barrels per day of output starting Jan. 1, the biggest single reduction on record.
The agreed cut was slightly higher than expected and will add to previous OPEC deals to cut 2 million bpd since September [
]. But oil traders focusing on the global economic downturn reacted coolly."It seems like, despite the fact that the economies of producer nations are clearly in trouble, they don't have the temerity to actually go ahead and do the kind of cut that would be really interesting to traders to turn this around," said Addison Armstrong, director of market research at Tradition Energy in Stamford, Connecticut.
Some traders had also hoped oil producing countries that are not part of OPEC might have weighed in. But neither Russia nor Mexico, which have cooperated with OPEC production cuts in the past, offered to reduce output.
The White House called OPEC's decision to cut production "short sighted" and said the oil cartel has an obligation to keep the market well supplied.
"It's not clear that OPEC's actions will be effective given the shift in global demand and the ability of OPEC members to meet the cartel's targets," said spokesman Tony Fratto.
"Regardless, OPEC has an obligation to keep the market well supplied and to consider the health of the global economy, so efforts to limit the benefits of lower energy prices are short sighted," he said.
OPEC, however, is desperate to halt the slide in prices with economists predicting 11 of OPEC's 12 members, as well as Russia and Mexico, will face budget deficits with crude oil at $40 a barrel.
Energy analysts said the cuts could bolster prices in the longer run if OPEC members comply and if demand falls less than expected in 2009.
"The biggest question about how effective this agreement will be is just how much demand will contract," said Sarah Emerson, director of Energy Security Analysis Inc in Boston. "I think OPEC is showing that they have strong intentions to support prices."
The slump in prices has already sent shock waves through oil producer countries and top companies, leading to cutbacks and delays in spending on key projects that had promised to boost future world output.
The soft market has also led oil refiners in the United States, the world's biggest energy consumer, to slow down fuel production to match weak consumer demand.
The U.S. Energy Information Administration said the nation's crude and refined fuel stockpiles rose last week as a demand slump led refiners to run less oil. [
] (Additional reporting by Christopher Johnson; Editing by Marguerita Choy)