TOKYO - In recent years, Toyota has edged closer to overtaking General Motors as the world's biggest automaker.

But now as GM and the entire U.S. auto industry teeter on the brink of collapse, Toyota and other Japanese carmakers are hardly rejoicing. They say the bankruptcy of any of Detroit's Big Three would spell serious trouble for them as well.

Should that happen, "the damage to our business is certain to be tremendous," Toyota Motor Corp. spokesman Hideaki Homma told The Associated Press on Monday. "The conditions for the U.S. auto market are extremely tough right now, and any additional negative is sure to make things worse."

One major problem is that Japanese carmakers in the U.S. share many of the same parts suppliers. If a Detroit automaker were to collapse, suppliers would likely follow, setting off a chain reaction that could would wreak havoc for Japanese production in the U.S., a vital market.

More broadly, the U.S. crisis could lead to huge job losses and further weaken consumer spending, especially for big-ticket items like automobiles. Together, the three big American automakers employ 239,000 workers in the United States. Counting other businesses that depend on the automakers, economists estimate that 2.5 million jobs would be lost if all three companies went out of business.

"Whether it is the impact on consumer confidence or the impact on the suppliers that we all share, having one or more of the major automakers in severe distress has consequences for the entire industry," said Simon Sproule, corporate vice president of global communications at Nissan Motor Co., Japan's third-biggest carmaker.

A possible advantage from a collapse of the U.S. auto industry could come only many years later — perhaps in a decade — when Japanese manufacturers would compete against weaker rivals in the U.S., especially if they further exploit their lead in green technology with hybrids or electric vehicles, said Koji Endo, auto analyst with Credit Suisse in Tokyo.

"But that's for the long, long term," he said. "For now, the situation is bound to get worse for the Japanese."

After the U.S. Senate last week rejected an auto industry bailout, the Bush administration is considering ways of providing emergency aid to General Motors Corp. and Chrysler LLC, which have said they could run out of cash within weeks without federal aid. Ford Motor Co. says it can survive 2009, but it has also asked Congress for a line of credit.

While Japanese automakers are in a far better financial state than their American counterparts, they are all getting battered in the shrinking U.S. vehicle market.

In November, when American auto sales plunged 37 percent to their worst level in more than 26 years, Toyota's sales sank 34 percent, Nissan's were down 42 percent and Honda Motor Co.'s fell 32 percent.

Vehicle sales in Japan and Europe are also waning, and even demand in developing economies in China, India and Latin America is weakening.

"This is a global crisis affecting the entire auto industry: No one is immune," said Nissan's Sproule. "And it is in everyone's interest to see a healthy auto industry that is able to manage through this crisis."

Toyota, Japan's top automaker that makes the Camry sedan and Prius hybrid, has already slashed its profit forecast for the fiscal year through March to 550 billion yen ($5.9 billion), or about a third of its previous year's earnings. Expectations are rife another downward revision is coming.

For now, there are even alarming signs the Japanese may be falling in the footsteps of the U.S. automakers, said Endo.

GM, which has already idled five factories this year, announced Friday it is temporarily closing 21 factories across North America. Toyota has also suspended production at several North American plants in recent months.

The region is critical for Japan's automakers — both Toyota and Honda sell more vehicles in North America than they do in Japan.

"There is absolutely no way in my view that the Big Three's woes can work as a plus for the Japanese automakers," said Tsuyoshi Mochimaru, analyst for Barclays Capital in Tokyo.

"So what if there might be a market-share increase some years ahead? The pie itself is shrinking," he added. "Sales volume is plunging. And that's why all the automakers are suffering."

So far this year, Toyota appears to be on pace to overtake GM in global vehicle sales. Last year, Toyota's group sales rose to 9.366 million vehicles, just shy of GM's 9.37 million.

Toyota's Homma notes that 15 or 20 years ago, when there was a backlash among some American politicians and consumers toward Japanese products, Toyota may have gotten criticized as benefiting from — or even causing — U.S. automaker's demise.

But these days, Toyota is no longer viewed as foreign, and consumers understand that Toyota employs American workers and purchases from American suppliers, he said.

"We are a member of the American auto industry," Homma said. "Without (a bailout), chaos is sure to come."