Washington (CNN) -- A government shutdown would not hamper the war efforts in Afghanistan and Iraq or the U.S. military efforts in Libya and Japan, the Pentagon insisted on Tuesday. But the Pentagon is digging in for a longer standoff with Congress over how to pay for those missions.
"We would retain the ability and the authority to continue to protect our vital interests around the world, to continue to safeguard the nation's security, to wage the wars we're fighting and the operations that we are conducting right now." Pentagon spokesman Geoff Morrell said, adding that the hope is a shutdown can be averted.
CNN's Chris Lawrence reported on Monday that U.S. service members could see their pay put on hold if there is an extended shutdown. Asked about this possibility at a Pentagon briefing on Tuesday, Morrell said there was no decision yet.
"We're working through it," Morrell said at a Pentagon briefing. "Haven't come to a determination yet. But, obviously, that's an area of concern for us."
The Pentagon is facing a budget battle on many different fronts: A possible government shutdown on Friday, the lack of a full spending bill for this year and a new barrage of questions from Congress about its spending money.
Part of the political turbulence comes with congressional frustration that President Obama acted first on Libya and consulted later with Congress. Like so much friction between the White House and Capitol Hill, it boils down to dollars.
Rep. Roscoe Bartlett, R-Maryland, has introduced legislation to force Defense Secretary Robert Gates and the administration to add up the expenses of the Libya mission and show specifically what budget cuts they will make to pay for them.
The bill is called the "Protect America From U.S. Military Expenses in Libya Act," for what Bartlett calls "an illegal war."
"I think almost everyone agrees the cost shouldn't be borne by taxpayers," Bartlett told Gates at a House Armed Services Committee hearing last week. Bartlett would exempt the Defense budget as well as the departments of Homeland Security and Veterans Affairs from the cutbacks.
"It shouldn't come out of the hide of Department of Defense," Bartlett said. "That hide is getting pretty thin, now, sir."
Gates seemed to balk at a timetable of reporting back to Congress by July 1. "I would have to consult with the White House and OMB on that," Gates said.
Sen. Mark Begich, D-Alaska, also was critical of Gates, wondering how the Pentagon was "moving and shifting" money around.
"It is my view that the Defense Department cannot just eat that cost," Gates said, reminding lawmakers that the first 10 days of the Libyan mission had cost about $550 million, with the hopes of scaling that back to $40 million a month as the U.S. stepped back and other countries stepped up. But Gates left himself some room to roam on costs.
"Again, I'm -- I'm just in the beginning of conversations with the White House and OMB on that," Gates said.
Begich and others don't seem reassured.
"It doesn't seem the administration has a plan for covering the costs," he said. And he's suggested that U.S. allies, NATO and possibly the Arab League pick up part of the U.S. tab. Gates sounded skeptical and pointed out that Saudi Arabia and Kuwait had provided the bulk of repayments to the United States for costs of the Gulf War.
"They (Saudi Arabia and Kuwait) clearly don't feel that kind of a direct threat today from Gadhafi, and so I think -- I think getting these guys to shoulder very much, if any, of the financial cost is a remote possibility," Gates said.
Begich said he's concerned that Congress doesn't know the details about Pentagon plans to move money around. "We need to know more about what those trade offs would be and how they impact operations in Iraq and Afghanistan and impact our troops well-being and readiness," Begich said in a statement released by his office.
Gates had said the money from $4 billion of "unrequested adds" might be used. The usual, politically charged word for that is "earmarks," money sought by individual lawmakers for pet projects. "That's where we'll look first," Gates told the senators.
Begich later raised objections. "As a member of the Senate, I have to disagree with his assertion only the administration is capable of determining how to use taxpayer money," Begich said. "Those member-adds are for U.S. projects to enhance national security -- to use them to pay for Libya doesn't do anything for our economy."
That unpredictability was echoed by Rep. Howard "Buck" McKeon, House Armed Services Committee chairman, at a session with journalists on Monday.
"The military is really being squeezed," the California Republican said in the conference room adjoining his offices. "All of these things were not in the budget. ... There are people who really want to cut back the defense budget and yet we expect them to carry out all these missions."
The additional expense for missions come as the Defense Department, like the rest of the government, is operating without a formal budget. The government is operating under short-term continuing resolutions, or CRs, that keep spending at last year's lower level.
"The CR is causing them lots of problems," McKeon said. "They can't start new projects, they can't end programs and it causes them to do what they would say are stupid things -- wasting money."
McKeon and other congressional leaders are hoping to create a separate, permanent appropriations bill for the Defense Department. McKeon predicted it would be done "very shortly."
Late last week, facing the House and Senate Armed Services Committees, Gates didn't hold back. "Frankly, I need help from the Congress. The Department of Defense needs help from the Congress," Gates said.
"If we're going to do all these things, we need the resources to do them. And under this continuing resolution, we're canceling ship deployments because we don't have the money to pay for 'em."