WASHINGTON — President Bush, trying to contain a brewing rebellion within conservative ranks, promised Friday to help Congress cut spending in other areas to offset the cost of Hurricane Katrina reconstruction.

Bush said he still intends to spend whatever it takes to finance the massive Gulf Coast rebuilding effort he unveiled in Thursday night's address to the nation. And White House officials acknowledged the government would cover most of the costs in the short term by running up the federal debt.

But the president ruled out tax increases to reduce the flood of red ink, and he said the Office of Management and Budget would help lawmakers trim other federal programs to offset reconstruction costs that independent analysts have predicted will top $200 billion.

"You bet, it's going to cost money," Bush said during a joint news conference with Russian President Vladimir Putin at the White House.

"The key question is to make sure the costs are wisely spent and that we work with Congress to make sure we are able to manage our budget in a wise way," he said. "And that's going to mean cutting other programs."

The president's remarks were aimed in part at GOP lawmakers and conservative activists who were expressing profound misgivings about what they perceive as an open-ended federal commitment to borrow and spend enormous sums to rebuild the city of New Orleans and nearby coastal communities in Louisiana, Mississippi and Alabama.

"This isn't the first time an American city has been devastated," said Pat Toomey, a former congressman from Pennsylvania who now heads the conservative Club for Growth. "We've had great disasters, and the federal government didn't always come in and rebuild these cities We shouldn't assume the only way to do this is through Uncle Sam."

Rep. Shelley Moore Capito, R-W.Va., expressed concern about the potential for wasteful spending in Bush's reconstruction plan. "We don't want to turn rebuilding the Big Easy into the Big Dig," she said, referring to the costly underground-highway project in Boston.

Hurricane Katrina reconstruction, Capito said, "is going to require efficiency, which is not something synonymous with the federal government."

The debate reflected a deep schism within the conservative community, pitting advocates of a limited federal government against supporters of a more expansive GOP agenda.

The president's promise to undertake a reconstruction effort roughly twice as expensive as the post-World War II Marshall Plan intensified the anxiety of fiscal conservatives who already rue the rapid increase in deficit spending since Bush took office.