White House Chief of Staff Bill Daley warned Sunday that the financial markets are starting to have doubts about the ability of Washington to strike a debt deal, as lawmakers scramble to come up with a plan before Asian stock markets open.

The Asian markets will start to open Sunday evening Washington time, ahead of the Dow opening in the U.S. Monday morning. U.S. officials are cognizant of the possibility that a failure to outline a path forward by then on how to raise the debt ceiling could roil the markets.

"We are now getting to a point where I think markets around the world will question whether the political system in Washington can come together and compromise for the greater good of the country," Daley said on NBC's "Meet the Press."

Aides will be darting in and out of meetings in the usually empty Capitol Sunday. Top leaders of the House and Senate will be conferring as well. House Speaker John Boehner, R-Ohio, said he wants to announce the outlines of a plan by 4 p.m. EDT Sunday.

Boehner met Saturday with President Obama to try again to find a balance of major spending cuts and revenue increases that could win passage in the GOP-controlled House and Democratic-controlled Senate. Also at the meeting were Senate Majority leader Harry Reid, Senate Republican leader Mitch McConnell, House Democratic leader Nancy Pelosi, Treasury Secretary Tim Geithner and White House budget director Jack Lew.

The four lawmakers met later in the Capitol, without Obama or his aides. Boehner is seeking as much as $4 trillion in cuts over a decade as a condition for raising the nation's debt limit. Reid accuses GOP leaders of intransigence, suggesting the two sides still have sharp differences.

Despite the looming deadline, White House and congressional officials said several proposals were still being discussed. A "grand bargain" would cut spending by up to $4 trillion over a decade and raise up to $1.2 trillion in new revenues. Other plans envision smaller revenue increases and spending cuts of $1.2 trillion or so.

All the proposals face a basic obstacle. Many House Republicans refuse to vote for higher tax revenues; most congressional Democrats consider higher revenues essential if government spending is to be cut so deeply.

Obama, Reid and Pelosi have said they will not support a proposal that does not solve the debt-ceiling problem at least through 2012.

The Associated Press contributed to this report.