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Leading senators on the Budget Committee clashed Tuesday over whether the Pentagon could bear even deeper budget cuts, with defense officials warning that additional reductions would hit jobs across the 50 states and affect national security.

Democratic Sen. Kent Conrad, the committee chairman, said that given the country's fiscal crisis more savings must be found in the core defense budget, and that it would be impossible to address the nation's deficit without doing so.

"I don't think that, end of the day, we'll have an alternative here," said Conrad, adding that if lawmakers don't find a way to save "it will be forced on us."

The panel's top Republican, Sen. Jeff Sessions, said, however, that America's budget can't be balanced with just Pentagon cuts. The escalating costs of entitlement programs must be addressed, he said.

Defense Secretary Leon Panetta, who was once chairman of the House budget panel, told senators that while he can find the planned savings of $487 billion over the next 10 years, any more than that would hamper the military's ability to meet future threats.

Doubling the amount of cuts, said Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff, would mean that "we would no longer be a global power."

Senators also argued that the military should reduce its installations overseas, pointing out that Americans generally dislike cuts to domestic health care or other programs, but favor cutting foreign aid.

Panetta and Dempsey said that they've cut almost 140 military facilities in Europe over the last few years, and are looking for additional savings. But Dempsey warned that such cuts must be made carefully because the U.S. looks first to European allies for support and assistance in times of war.

Panetta raised the prospect of deeper cuts hitting the states, echoing his previous warnings of possible harm to military installations all across the country and the jobs they provide.

The budget agreement that Obama and congressional Republicans reached last August calls for the initial $487 billion in cuts over a decade. But, more troubling to Panetta and lawmakers is the likelihood that automatic, across-the-board cuts will kick in come January unless Congress can come up with at least $1.2 trillion in budget savings.

If that happens, the Pentagon would face an additional $492 billion in cuts.