Published: Apr 11, 2011 4:24 PM EDT
Updated: Apr 11, 2011 1:26 PM EDT

WASHINGTON- The Pentagon said Monday the military intervention in Libya cost the U.S. an extra $608 million in the first few of weeks of the operation. Spending is down significantly, though not as much as expected.

Defense Department spokeswoman Navy Cmdr. Kathleen Kesler said it will take several weeks to tally exactly how much has been spent. But $608 million is the price tag officials have estimated through April 4 - or for 17 days of the mission, the most recent figures available.

The estimate shows a large drop from what the U.S. spent in the early days of the multinational operation that started March 19 - roughly $55 million a day in the first 10 days, then about $8.3 million a day in the seven that followed.

Still, very rough projections late last month estimated costs would decline even more than that as the U.S. handed lead of the operation to NATO. The alliance would also conduct most of the bombing missions. Officials didn't explain what caused the higher-than-expected rate of spending. It's possible at least part is due to the fact that the full transition to NATO went a little slower than expected.

It is the second time the Pentagon has released costs for setting up the no-fly zone in the North African nation and protecting civilians from strongman Moammar Gadhafi as he resists a movement to oust him.

Officials late last month said the added spending from March 19 through March 28, the first 10 days of the intervention, was $550 million. About 60 percent was for munitions. The remaining costs were for "higher operating tempo" of U.S. forces and of getting them there.

At that time, Kesler said that future costs were "highly uncertain" but that officials estimated they'd see added costs of about $40 million over the following three weeks as U.S. forces reduced their mission to providing refueling, intelligence and other support. But rather than $40 million over three weeks, the cost was $58 million over seven days, according to the new figures through April 4.

Officials call it extra costs because it doesn't include complete spending such as paychecks for U.S. sailors, airmen and other forces, who would have been deployed somewhere in the world anyway.

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