The latest bleak US unemployment figures makes helping the big three car firms even more urgent, a leading politician has warned.
GM, Ford and Chrysler bosses faced Congress for a second day of questions, but no bailout has so far been agreed.
The committee chairman, Democrat Barney Frank, warned that to do nothing "would be a disaster".
The carmakers have faced considerable opposition to their plea for a $34bn (£23bn) rescue plan.
Friday saw the latest US jobless figures, and the news that US companies axed 533,000 jobs in November, the most in 34 years. The unemployment rate rose to 6.7% from 6.5% in October.
Adding to these figures, GM said on Friday it would lay off 2,000 more workers early next year in the US, because of falling car sales.
This is about survival at this point in time - there's going to be, unfortunately, losses
Ron Gettlefinger, United Auto Workers President
Mr Frank said the data showed that helping the troubled car industry had become a greater priority.
"For us to do nothing, to allow bankruptcies and failures in one or three of these companies in the midst of the worst economic situation since the Great Depression, it would be an unmitigated disaster."
But he said the US was being "held hostage" by the political debate raging over how to help Detroit's carmakers.
In a statement at the White House, President Bush said he was "concerned about the viability of the automobile companies".
"Likewise I am concerned about taxpayers' money being provided to those companies that may not survive," he said.
Broad consensus exists between Congress and the Bush administration that the carmakers need help, but officials have so far been unable to reach agreement on how to do it, with some lawmakers opposed to doing anything at all.
DETROIT'S BIG THREE
US November car sales compared with a year earlier:
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