As the House continued its marathon debate Thursday over a bill to fund the federal government, House Speaker John A. Boehner (R-Ohio) acknowledged that Congress might not reach agreement over spending cuts before the government runs out of money next month.

But Boehner ruled out passing a temporary funding resolution to keep the government operating unless it contained at least some spending cuts. Democratic leaders in the Senate said that position increased the risk of a federal shutdown.

The government is currently operating under a temporary funding measure, which expires March 4.

The Senate is unlikely to approve its version of the legislation until next month, and Democrats who control the chamber want to approve another extension, perhaps lasting a few weeks, to keep agencies operating at last year's levels while the two chambers work out their differences. They said they are prepared to meet Republicans partway on overall reductions for the year.

"There will be some additional cuts, we know that," said Sen. Charles E. Schumer (N.Y.), a senior member of the Senate leadership. He added that those cuts would come only as the result of "fair negotiations."

Boehner declared Thursday that he would not allow the House to consider a temporary funding measure that did not reduce spending. "I am not going to move any kind of short-term [resolution] at current levels," he said.

It is not clear how much Republicans will demand to be cut to keep the government open, but both sides view this debate as a preview to more intense negotiations over spending. Many House Republicans - including the 87 GOP freshmen who campaigned on reducing spending to 2008 levels - have made the issue a priority and are pressuring their leaders not to compromise.

Meanwhile, the House continued moving Thursday toward final passage of its federal-spending bill, with a short-term victory all but assured for Republicans. They were less sure of when they could declare it.

With hundreds of amendments still on the docket, House GOP leaders abandoned their initial goal of finishing the government funding bill by mid-afternoon Thursday. Instead, lawmakers debated until just after 1 a.m. Friday - their third consecutive session to go beyond midnight - and plan to vote Friday on a spending package that would trim $61 billion in agency budgets for the final seven months of 2011.

This arrangement was in large part by design, because Boehner has pledged to run a wide-open process on the House floor that allows many, many amendments to be offered - a sharp contrast to how Democrats and his fellow Republicans ran the floor the previous 16 years.

One result of that process, though, is that the House debated its bill until after 3 a.m. Thursday.

Boehner said the result is certain, however. Echoing the words of the 41st president, Republican George H.W. Bush, he added, "When we say we're going to cut spending, read my lips: We're going to cut spending."

It's an open question as to how much spending Boehner can really cut, given President Obama's veto threat and the fact that Senate Democratic leaders have labeled the GOP plan as "draconian" and drawn up with a "meat cleaver" because it cuts so deeply into government programs.

Boehner accused congressional Democrats of wanting a government shutdown so they can pin the blame on Republicans in a replay of the mid-1990s Clinton-era shutdowns.

Senate Majority Leader Harry M. Reid (D-Nev.) rejected that notion and accused Boehner of threatening to close the government to appease a vociferously anti-government wing of the GOP conference. "We're terribly disappointed Speaker Boehner can't control the votes in his caucus to prevent a shutdown of government, and now he's resorting to threats to do just that, without any negotiations," Reid told reporters.

sonmezf@washpost.comStaff writer Felicia Sonmez contributed to this report.