The Big Three automakers must give Congress a plan by Dec. 2 showing how they would use federal money to remain viable businesses, Democratic leaders said. If the companies do so, Congress could return for a second lame-duck session days later.

The auto companies are seeking the money simply to pay their bills.

"Until they show us a plan," House Speaker Nancy Pelosi (D., Calif.) said, "we cannot show them the money."

Failure to reach agreement on aid for the automakers came despite a last-ditch effort yesterday by a bipartisan group of congressional allies of the car industry to craft legislation.

The group sought to push an idea, endorsed by the White House, that would have modified an existing loan program that was created to help the automakers develop advanced technologies and retool factories to produce more fuel-efficient vehicles.

House leaders said repeatedly that such a solution would not be acceptable.

Sen. Carl Levin (D., Mich.) said he was disappointed that congressional leaders did not allow a vote on the measure. He said he believed it would have passed.

At a news conference with Pelosi and other top congressional Democrats, Senate Majority Leader Harry Reid (D., Nev.) said that "we do not have the votes" to pass such a measure.

The main reason, he said, is that in House and Senate hearings this week, the chief executives of the Big Three "have not been able to convince the Congress or the American people that this government bailout will be its last."

Reid said that before Congress can extend help to General Motors Corp., Ford Motor Co. and Chrysler L.L.C., their executives "have to get their act together" by coming up with a plan and showing accountability.

"We're prepared to come back into session the week of Dec. 8 to help the auto industry, but only if they present a viable plan that gives us, the Congress, the confidence that taxpayers and the autoworkers will be well served," he said.

Under the Democratic leaders' proposal, Rep. Barney Frank (D., Mass.) and Sen. Christopher J. Dodd (D., Conn.) would be charged with reviewing the automakers' plan and, if necessary, holding hearings on it during the first week of December.

Frank, who chairs the House Financial Services Committee, told reporters that "in the minds of the media, Congress can operate at one of two speeds - either way too slow or much too fast."

If lawmakers passed a bailout for the auto industry right away, he said, "I could write the stories for tomorrow: 'In a rushed, barely examined commitment of many, many more taxpayer dollars, Congress today leapt into an abyss.' "

He said there was "widespread dissatisfaction" with the perceived failure of the recipients of a $700 billion financial-industry bailout to use the money the way Congress intended.

The White House, meanwhile, came out in support of a bipartisan proposal crafted by senators from auto-manufacturing states. The proposal was presented by Levin, the senior Democratic senator from Michigan, and Sen. Christopher Bond (R., Mo.).

"The president has insisted that help for the auto industry be contingent on the industry making the changes needed to be viable," White House spokeswoman Dana Perino said in a statement. "We are pleased the Democratic leadership now agrees that is necessary."

The carmakers have been hit hard by poor sales and choked credit and are battling to stay afloat through year's end.

The leaders of the Big Three have painted a grim picture of their financial position. They burned through nearly $18 billion in cash reserves during the last quarter - about $7 billion at GM, almost $8 billion at Ford and $3 billion at Chrysler. GM and Chrysler have said they could collapse in weeks.

The stakes are high. The Detroit automakers employ a quarter-million workers, and more than 730,000 other workers produce materials and parts that go into cars. About a million more people work in auto dealerships nationwide.

If just one of the automakers declared bankruptcy, some estimates put U.S. job losses next year as high as 2.5 million.

Earlier yesterday, United Auto Workers chief Ron Gettelfinger made an impassioned appeal to Congress and President Bush to approve a $25 billion bridge loan to GM, Ford and Chrysler before adjourning, saying the companies otherwise could face dire consequences.

"Inaction is simply not an option," he said. "Without immediate action, we could see - and I stress 'could see' - the collapse of one or more of the domestic automakers by the end of the year."

Gettelfinger said "the costs that would flow from that are simply too great."