Tense talks are continuing on a bill to provide financial aid to the auto industry as the White House pushes tougher consequences than congressional Democrats embrace for failure by the carmakers to bring costs under control.

The Bush administration would allow a ‘‘car czar’’ envisioned in the legislation to force the companies into bankruptcy if they weren’t doing enough to cut labor costs, restructure their debt and downsize to stay afloat.

At the same time, the head of the United Auto Workers, Ron Gettelfinger, signaled that his union might demand an equity stake in General Motors Corp., if asked to give up more.

The fast-paced developments come amid an environment of general economic instability, the Congress and the presidency both in transition, a ricocheting Wall Street and the Federal Reserve Board, Treasury and other agencies fighting to steady the reeling financial industry.

House Speaker Nancy Pelosi said she supports the concept of a federal overseer of any rescue plan, saying she lacked confidence the heads of the car companies could solve the problem if ‘‘left to their own devices.’’

Pelosi appeared on morning television Tuesday after a night of intense Capitol Hill discussions aimed at narrowing the differences over a $15 billion bill that would, among other things, rush short-term loans to the industry. The plan would require that the Big Three reinvent itself to survive — and that it pay back the government if it doesn’t. The package could come to a vote as early as Wednesday.

Pelosi said she thought taxpayers should consider it ‘‘a second chance’’ rather than a bailout.

Deputy White House press secretary Tony Fratto said Tuesday, ‘‘We made progress and hope to continue making progress. We want to move quickly, but it’s important that we get the policy right.’’

Cash from any such rescue plan would immediately be plowed into General Motors Corp. and Chrsyler LLC. Ford Motor Co. has said that it does not have an emergency cash-flow problem and that it would not ask for short-term assistance.

In testimony before Congress last week, General Motors and Chrysler, which have said they are weeks from collapse, made it clear they would need a total of $14 billion to $15 billion to survive through early 2009.

‘‘We do not face a near-term liquidity issue, and we will not be seeking a short term bridge loan,’’ the company said in a statement Monday night. ‘‘But Ford fully supports an effort to address the near-term liquidity issues of GM and Chrysler, as our industry is highly interdependent and a failure of one of our competitors could affect us.’’

Robert Lutz, GM’s vice president of global product development, also said he could accept a federally appointed czar to supervise implementation of a restructuring plan.

‘‘Well, whether we need it or not, I think it’s reasonable that when the federal government steps in with taxpayer money, they’re not going to–they’re not going to lend us the money and just say, ‘Do the best you can with it and tell us when you need more.’ Obviously, there’s going to be some kind of oversight and I think that’s a reasonable thing to expect,’’ he said on CBS’s ‘‘The Early Show.’’

The measure being discussed in Congress would put a government overseer named by Bush in charge of setting guidelines for an industrywide overhaul, with the power to revoke the loans if the automakers fail to do what’s necessary to become viable.