US President Barack Obama was to address the nation Friday after giving divided lawmakers 24-36 hours to strike a deal to avert a possible August debt default that has sparked global alarm.
After days of tense negotiations and downgrade warnings from credit ratings agencies Moody's and Standard & Poor's, Obama on Thursday told lawmakers "it's decision time" and set a press conference for Friday at 11:00 am (1500 GMT).
The ratings agencies have warned the United States risks losing its sterling Triple-A debt rating and leading US creditor China, Wall Street titan JPMorgan Chase and the Federal Reserve have also sounded the alarm.
"I want to do the largest deal possible," a well-placed Democratic official quoted Obama as telling Democratic Senate leaders and their Republican House counterparts during a fifth straight day of White House crisis talks.
Obama ruled out a short-term fix to let the negotiations run beyond August 2, when cash-strapped Washington will lack money to pay for key services, and declared: "It's decision time. We need concrete plans to move this forward."
The Democratic official and Republican legislative aides said Obama had given the leaders 24-36 hours to get a sense from their rank-and-file what could pass in Congress, and left open the possibility of weekend talks.
Economists and finance and business leaders have warned that failure to raise the US debt ceiling above the current $14.3 trillion by August 2 could send shock waves through a world economy still reeling from the 2008 collapse.
Republicans, whose votes Obama needs to raise the congressionally set limit, have demanded sweeping spending cuts in return while rejecting calls from the White House and Democrats for tax hikes on the rich and corporations.
"We're probably not going to meet tomorrow, this group. But we're going to continue to discuss the way forward over the next couple of days," Republican Senate Minority Leader Mitch McConnell told reporters on Thursday.
Obama said he hoped for "a big deal" previously described as running about $4 trillion dollars in spending cuts, but said a smaller $2 trillion deal was possible, the Democratic aide said.
A third option was "to do significantly less on the deficit while still ensuring a long-term increase in the debt limit" to beyond the November 2012 elections in which Obama seeks a second term, the aide said.
US Treasury Secretary Tim Geithner told the group that skittish world markets believed "the debt ceiling must be raised, and we must put in place a plan to deal with our deficit and debt," according to a senior Republican aide.
Republican House Speaker John Boehner seized on that message to warn that "nothing the administration is offering to this point will resolve our debt problem" and pressed Obama to cut spending, the aide said.
Democratic House Minority Leader Nancy Pelosi said House Democrats favored a "grand bargain" to cut some $4 trillion while averting a default and protecting cherished social safety net programs.
The White House and key lawmakers seemed to be rallying behind efforts by McConnell and Democratic Senate Majority Leader Harry Reid to craft a complex legislative escape hatch to avert a default, cut spending and avoid tax hikes.
McConnell's proposal would effectively let Obama raise the debt ceiling with support just from Democrats, who would shoulder the political responsibility but get to protect social programs.
"This remains a fallback option," a Democratic aide said.
Republicans would be able to vote against raising the debt ceiling, as many "Tea Party" conservatives have vowed to do no matter what, and would be in a strong position to enforce their fierce opposition to tax hikes on the rich.
"I have no idea," if it can pass the House, but it "might look pretty good a couple of weeks from now," Boehner told reporters.
Republicans embraced calls for fiscal discipline when Obama took office in January 2009, after years of playing down swelling US deficits, approving massive tax cuts, and rejecting calls to pay for the Iraq and Afghanistan wars.
But a new opinion poll by Quinnipiac University found the US public more ready to blame Republicans than Obama by a 48 percent to 34 percent margin in the event the talks collapse.
Washington hit its debt ceiling on May 16 and has used spending and accounting adjustments, as well as higher-than-expected tax receipts, to continue operating normally, but can only do so until August 2.