DETROIT -- General Motors, battling "unprecedented economic and credit market turmoil,'' reported its fifth straight quarterly loss today and warned that it may not have enough cash to operate by mid-2009.

GM ended the third quarter with $16.2 billion in cash on hand, down from $21 billion on June 30.

The net loss was $2.5 billion, including one-time gains and charges. Before those special items, GM reported an adjusted loss of $4.2 billion. Revenue fell $5.8 billion, to $37.9 billion, and global unit deliveries dropped 11 percent.

The company also said it had called off merger talks with Chrysler LLC.

GM said it has identified ways to boost liquidity by an additional $5 billion by the end of next year, on top of $15 billion announced in July.

"Even if GM implements the planned operating actions that are substantially within its control, GM's estimated liquidity during the remainder of 2008 will approach the minimum amount necessary to operate its business," the company said in a statement.

"Looking into the first two quarters of 2009, even with its planned actions, the company's estimated liquidity will fall significantly short of that."

7,000 jobs slashed

The steps include $2.5 billion in reduced capital spending, to $4.8 billion, and $1.5 billion in structural cost reductions. Counting measures taken in July, more than 7,000 salaried and contract positions are being eliminated. GM plans to trim spending on salaries by $500 million.

The results compound the challenges of CEO Rick Wagoner and the Detroit 3, which are petitioning Washington for low-interest loans to survive plunging sales and the worst global financial crisis since the Great Depression.

Wagoner reiterated today that bankruptcy is not an option.

"The consequences of bankruptcy could be dire and beyond just General Motors,'' he said. "We will take whatever actions we can to avoid it."

Also today, Ford Motor Co. posted a $3.0 billion after-tax operating loss for the third quarter and told of plans to further cut costs and preserve cash. Both automakers said the global market will worsen next year.

GM forecast industrywide U.S. sales of 11.7 million next year, the lowest since 1982 and about 5 million below this decade's annual average through last year. In 2010, sales are expected to rise to 12.7 million.

When it announced its cash-saving plan in July, GM based its assumption on annual sales staying above 14 million.

Shares of GM today closed down 9.2 percent to $4.36 on the New York Stock Exchange.

October sales plunge

GM, which hasn't posted an annual profit since 2004, reported a 45.1 percent drop in October sales as industrywide demand fell to its lowest level in 25 years. The company's U.S. sales are down 20.4 percent through October compared with a year earlier.

The GMAC finance unit, now 49 percent owned by GM, accounted for $1.2 billion of GM's loss.

"Retail financial originations have been reduced by about 50 percent," GM CFO Ray Young said in a conference call. "There's been reduced capital availability for lease originations, and as a result there's been increased wholesale floorplan financing rates."

In the third quarter of 2007, GM posted a net loss of $38.98 billion, most of it because of tax-related noncash charges.

S&P downgrade

GM's cash burn prompted Standard & Poor's to lower its debt rating on GM further into junk status, from B- down to CCC+.

"We now believe GM will use much more cash this year than our previous estimate of as much as $16 billion in its global automotive operations," said Standard & Poor's credit analyst Robert Schulz in a statement.

"This will include cash restructuring costs and costs related to bankrupt former unit Delphi Corp. This cash use may continue unabated in the early part of 2009, even as the company continues to aggressively slash costs and conserve cash.

"GM's cash balances as of Sept. 30, 2008, were $16.2 billion; the company has stated that it needs $11 billion to $14 billion to operate."