'I'm thinking through, you know,' Bush said. 'It needs to get done relatively soon.'

Bush agreed to consider tapping the $700 billion Wall Street rescue fund after Senate Republicans last week blocked a compromise bill to provide automakers with $14 billion in aid.

Senior Treasury Department officials, who have been studying GM and Chrysler's books since Friday, briefed Bush on their efforts this week, a person familiar with the matter said.

They have been asking detailed questions of the automakers and their financing units, GMAC Financial Services and Chrysler Financial, which make loans to consumers.

After Chrysler's announcement about the plant shutdowns, White House spokeswoman Dana Perino reiterated the administration's commitment to act.

'It's clear that the automakers are in a very fragile financial condition and they're taking steps to deal with it,' Perino said in a statement. 'We're aware of their financial situation and are considering possible policy options to provide assistance in an appropriate way.'

A decision about how much aid to give the automakers and how to do it is complicated as the Treasury Department also weighs aid for Chrysler Financial and GMAC. GM still has a 49 percent stake in GMAC; the remainder is owned by Cerberus Capital Management LP. Cerberus also is the majority owner of Chrysler Holding Corp., which includes the automaker and Chrysler Financial. GMAC is working to raise enough capital to become a bank holding company, which would allow it to tap the Wall Street bailout money, known as the Troubled Asset Relief Program. GMAC has warned it is at significant risk of default if it doesn't get bank status by Dec. 31.

GMAC needs $30 billion in capital and had $9 billion on hand at the end of the third quarter. About $20.1 billion in notes have been tendered as part of its effort to swap $38 billion in debt for equity. GMAC extended the deadline until Friday to raise additional funds -- the fifth time it has done so.

GMAC must also raise $2 billion in new capital, and has raised $750 million of that from shareholders. 'We're working diligently to meet these targets,' GMAC spokeswoman Gina Proia said Wednesday.

Chrysler Financial Chief Financial Officer Thomas Gilman told dealers in a Dec. 12 letter that it had been in talks with Treasury to access TARP funds 'for over a month.' Only about $15 billion is remaining in the first $350 billion of the $700 billion and Treasury needs permission from Congress to use the rest.

Gilman warned dealers that the finance unit could be forced to suspend financing vehicle inventories if dealers kept withdrawing large amounts of their money from of an account that is used to fund loans to them.

Gilman said withdrawals from the account have topped $1.5 billion since July -- or about $60 million daily.

As the automakers wait for a bailout deal, they are trying to conserve cash.

The delay of GM's engine plant in Flint is not likely to impact the launch of the Cruze or the Volt in 2010, according to the company and analysts.

'The engines can be built at any of several existing plants that GM has overseas,' said Jim Hall of 2953 Analytics LLP. 'They wanted to build it in the States to stabilize the transfer price.'

The plant actions by GM and Chrysler come amid growing fears that auto sales will fall faster in 2009 that previously expected.

Citi said Tuesday it was cutting its vehicle sales estimates for this year to 12.7 million vehicles, from 12.85 million, and to 10.8 million units in 2009.

The auto industry has been battered by a sharp downturn in the U.S. economy.

GM, Ford and Chrysler have responded by slashing factory output and jobs, but all three companies still carry enormous overhead costs and other financial obligations that drain cash reserves.

The auto industry crisis is not limited to the United States and other nations have stepped in to help automakers cope.

The Canadian government said Wednesday it could boost a bailout of the Canadian affiliates of U.S. automakers beyond a $2.8 billion package suggested this week.

Treasury officials hope to announce a bailout deal for Detroit's automakers by Friday, but warned it could slip to Saturday or later.

Automakers are nervous that if an announcement is delayed past Monday, suppliers and the stock markets could react negatively.

GM and Chrysler both could be forced into bankruptcy in early January when large supplier bills come due, Standard & Poor's said in a report on Friday. GM says it needs $4 billion this month and $4 billion next month -- part of an $18 billion request. Chrysler said it needs $4 billion to survive through March 31. In total, Detroit's Big Three face about $13 billion in supplier payments in early January.

Ford wants a $9 billion stand-by line of credit from the government but has said it would not tap it unless the economy worsened.

The head of the National Automobile Dealers Association on Wednesday urged Bush to act quickly, as did Rep. John Dingell, D-Dearborn. Groups of House and Senate Republicans in Congress sent separate letters urging Bush to not grant the bailout.

'A lot of people are depending on the White House to provide the bridge loans to prevent a collapse of the auto industry,' NADA chairwoman Annette Sykora said. 'We need action now.'