Republicans scaled back plans for deep cuts in US government spending as they took power in the House of Representatives today, diluting a key promise that helped them to victory in November's election.
The new speaker of the House also signalled the party could work with the administration of President Barack Obama to avert a debt crisis in the coming months.
"Our spending has caught up with us, and our debt will soon eclipse the size of our entire economy. Hard work and tough decisions will be required," Republican John Boehner said.
Mr Boehner was elected House speaker as the new Congress convened, taking over from Democrat Nancy Pelosi.
Republican control of the House and a larger minority in the Senate usher in a new era of divided government after big election gains spurred in part by high unemployment and the large $1.3 trillion deficit.
But Obama's Democrats still control the Senate and can block the Republican agenda, which includes a plan to repeal the president's landmark healthcare reform and a crackdown on Wall Street.
The incoming House budget chief, Republican Paul Ryan, told NBC's Today program that a Republican campaign promise to cut $100 billion in spending this year had been "compromised" by the momentum of spending already under way.
The actual cuts put forward could be "substantially less" than $50 billion, a House Republican aide said, because the fiscal year will be halfway through by the time Republicans get a chance to affect spending.
A deal on taxes in December showed Mr Obama and the opposition can work together but there are many thorny issues to deal with as the United States recovers slowly from its worst recession since the 1930s.
Mr Ryan, the incoming House budget chief, said he will seek spending concessions from the Obama administration in exchange for any increase in the national debt ceiling.
"I'm not interested in raising the debt ceiling on the hope that a promise will be fulfilled at a later time," Mr Ryan told MSNBC.
"I'm only interested in raising the debt ceiling if we get concessions on spending, on real controls to get our fiscal situation turned around and headed in the right direction."
While Republicans are under pressure from the fiscally conservative Tea Party movement to slash spending, Mr Ryan's comments suggested they are willing to work with Obama on raising the debt level, although fights could still break out before the issue comes to a head in March or April.
At the White House, spokesman Robert Gibbs urged Republicans to approach the debt limit vote "in a way that's responsible and in a way that doesn't threaten the full faith and credit of our government."
The two parties are headed for their first big clash next week, when Republican House leaders plan a vote on repealing Obama's healthcare overhaul. The effort looks doomed to failure in the Democratic-led Senate but the vote could set the tone for a combative first few months.
Ms Pelosi said Congress should focus on what largely cost Democrats control of the chamber in November's election - the near double-digit jobless rate.
"Our most important job is to fight for American jobs. And so Democrats will judge what comes before Congress by whether it creates jobs, strengthens our middle class, and reduces the deficit - not burdening future generations with debt," she told the opening session of the new Congress.
President Obama will have a chance to offer his own vision early in the year when he makes a State of the Union speech to Congress and unveils a new budget, and he could propose some form of tax reform as a way to reach a major deal with Republicans.
Reuters