WASHINGTON -- Bipartisan opposition is emerging in the Senate to a plan by House lawmakers to spend $550 million for additional passenger jets for senior government officials.

The resistance to buying eight Gulfstream and Boeing planes comes as members of both chambers of Congress embark on the busiest month of the year for official overseas travel. The plan to upgrade the fleet of government jets, which was included in a broader defense-funding bill, has also sparked criticism from the Pentagon, which has said it doesn't need half of the new jets.

Two Missouri senators, Democrat Claire McCaskill and Republican Christopher Bond, said they would oppose funding for the jets when the legislation is taken up by the Senate in September.

"The whole thing kind of makes me sick to my stomach," said Mrs. McCaskill in an interview Sunday. "It is evidence that some of the cynicism about Washington is well placed -- that people get out of touch and they spend money likes it's Monopoly money."

Sen. John Thune (R., S.D.) says the planned purchase "is a classic example of Congress being out of touch with the realities of deficit spending."

The Obama administration had sought $220 million to buy four passenger jets, including two that are currently being leased by the Air Force, to replace a fleet of older planes. Before leaving town for the August break, House lawmakers doubled the aircraft order to eight, at a total cost of $550 million.

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