In his speech Thursday, Mr. Bush made clear that he wanted to avoid a “disorderly bankruptcy” because of “what it would do to the psychology of the markets.” But he also said he was “worried about putting good money after bad,” and suggested he would only approve a plan that allowed the auto companies to “become viable in the future.”

Mr. Bush’s comments, a month before he leaves office, made clear that he was worried by the idea of returning to Texas amid more economic chaos and the surge in unemployment that a collapse of the companies could cause.

“The autos obviously are very fragile,” he said. He added that he was concerned about what President-elect Barack Obama would face on Jan. 20. “I believe that good policy is not to dump him a major catastrophe in his first day of office,” he said.

What the White House appears to be envisaging is a package deal of concessions  and an injection of money from the TARP, the $700 billion financial bailout fund  to keep credit flowing for G.M. and Chrysler.

Taxpayer loans, the White House has said, would have first priority over all other debt. Ms. Perino said the goal was to “try to come up with something that would protect the taxpayers but not allow a collapse that would hurt everybody in America.”

But for Mr. Bush, that could be difficult to negotiate. If the autoworkers’ unions conclude they are likely to get a better deal from Mr. Obama, they are likely to stall negotiations and settle for a shorter-term loan.