WASHINGTON -- The administration of U.S. President Barack Obama is canceling NASA's current space shuttle replacement- and lunar exploration-plan and is prepared to fight any congressional effort to save it, the nation's top budget official said Jan. 31.  

The president's budget, officially sent to Congress Monday morning, confirms what officials had stated during a teleconference with reporters one day before: White House Office of Management and Budget Director Peter Orszag and White House Communications Director Dan Pfeiffer stated Obama's plan to kill NASA's Constellation program, a five-year-old effort to replace the aging space shuttle fleet with new rockets and spacecraft optimized to return astronauts to the Moon.

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"...[W]e are proposing a cancellation of the Constellation program at NASA even while making other investments in long range [research and development] there, which again is a significant step," Orszag said in response to a reporter's question about the tough choices Obama faced in drafting his 2011 spending plan.

The key elements of Constellation include the Orion crew capsule, its Ares 1 launcher, a larger rocket dubbed Ares 5 and the Altair lunar lander. Obama's top-line spending proposal for NASA is expected to increase slightly over the 2010 appropriation of $18.7 billion and would including some funding for an alternative means for transporting crews to and from the international space station.

Orszag said that in addition to research and development, NASA's proposal invests in "advance robotics and other steps that will help to inspire Americans and not just return a man or a woman to the Moon but undertake the longer range research that could succeed in human spaceflight to Mars."

Facing a federal deficit of $1.26 trillion in 2011, Obama is proposing a three-year freeze on most non-defense discretionary spending, a move the president believes will save $250 billion over the next 10 years, Orszag said. In addition, the White House is proposing more than 120 program terminations, reductions and efficiencies that together are expected to save $20 billion in 2011, Orszag said.

"You're going to see a whole variety of measures that curtail spending and activity in some areas while investing more in others," he said. "And again within the non-security discretionary sphere, achieving that overall cap."

In response to a reporter's question about congressional opposition to proposed program cuts that could lead to job losses in some states, Pfeiffer said the White House would fight special interests on Capitol Hill.

"We don't expect that this is going to be easy," Pfeiffer said. "There was a lot of opposition to some of the cuts that we proposed last year. And we had I think a historically very successful rate about 60 percent of the cuts we proposed were actually enacted into the law."

Pfeiffer said some funding reductions not enacted in the prior year budget would be evident in Obama's 2011 spending plan.

"Some of those cuts we didn't get are back in this budget and we're going to continue pushing for them because we don't believe that just because it has a powerful constituency, either on the Hill or on K Street, wasteful programs should continue to exist," Pfeiffer said.

When asked by a reporter what he would say to federal workers whose jobs could be eliminated if the president's 2011 budget is enacted, Orszag said the spending proposal would expand the federal workforce in some areas, including defense, homeland security and veterans affairs.

"In addition, we have a significant effort under way and the budget includes additional funding to expand our acquisition workforce to oversee the roughly half a trillion dollars in federal contracts each year," Orszag said. "In most cases, these agencies, you'll see tomorrow the agencies have stepped forward with a sensible approach to achieving this overall cap."

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