TOKYO (AFP) - Formula One was left reeling Wednesday as Toyota became the latest automaker to quit the glamour sport in response to the economic crisis, just days after tyre manufacturer Bridgestone pulled out.

Toyota said its decision to quit after this year's season, which ended Sunday in Abu Dhabi, reflected "the current severe economic realities."

Honda and Germany's BMW have already exited F1 to cope with the credit crunch. Toyota's withdrawal leaves no Japanese automaker left in the high-octane motorsport, raising fresh fears for its future.

The company said no decision had been made on whether to sell or disband the team, which has not won a Grand Prix since its 2002 debut on the F1 circuit and finished this season ranked fifth in the constructors championship.

"It was a tough decision because we are betraying the expectations of fans," Akio Toyoda, a racing enthusiast and grandson of the automaker's founder, told a news conference.

"I apologise to our fans from the bottom of my heart. I made the decision myself."

He ruled out supplying engines to other teams, saying: "In terms of Formula One, we will make a complete withdrawal."

Toyota is ready to ask rival teams to accept its F1 racers Kazuki Nakajima and Kamui Kobayashi, said team principal Tadashi Yamashina.

"If possible, I will let Nakajima and Kobayashi race in other teams as the two have reached such high levels," Yamashina said, wiping tears from his eyes with a handkerchief while sitting next to a sullen Toyoda.

While F1 attracts millions of viewers, the amount of money it costs to run a team -- estimated at hundreds of millions of dollars a year -- means it has become an unaffordable luxury for cash-strapped Japanese manufacturers.

The sport has lurched from crisis to crisis in recent years, including financial troubles, a Renault race-fixing scandal and a threat by a clutch of teams earlier this year to form a breakaway series over a proposed budget cap.

Facing a collapse in worldwide car sales, Toyota had already pulled out of hosting the Japanese Grand Prix at its Fuji Speedway circuit from next year.

On Monday Bridgestone said it would end its contract as the official tyre supplier to F1 -- joining an exodus of Japanese auto firms from world motor sports.

Honda announced in December its shock withdrawal from F1, selling its team to former principal Ross Brawn -- reportedly for just one British pound.

Brawn driver Jenson Button of Britain has since been crowned the new F1 champion, with the team at the top of the constructors standings.

Suzuki and Subaru meanwhile have withdrawn from the world rally championship, while motorcycle maker Kawasaki has exited the MotoGP and Mitsubishi is quitting the Dakar Rally despite a dozen victories.

Toyota's decision to exit F1 comes as the global economic downturn forces Japanese automakers to slash costs and step up their focus on environmentally friendly cars such as petrol-electric hybrids.

"Not only Toyota, but all automakers, are now under pressure to concentrate their investment in green technology," said Mamoru Kato, an auto analyst at Tokai Tokyo Research Centre.

"Toyota launched the F1 business in an effort to boost sales in Europe by improving its brand image there, but the impact appears to have been smaller than expected," said Kato.

Toyota overtook US rival General Motors in 2008 as the world's top selling automaker but it fell into the red for the first time in the year to March 2009 and expects another loss this year.

The Japanese maker, which is due to announce its interim financial results on Thursday, has idled plants and slashed thousands of jobs as it tries to weather its biggest ever crisis.

"There was a big debate in our company on whether we should continue F1 or not," said Toyoda. "We have done what we can and the team worked very hard. But considering the future, we had to make this decision."

He said Toyota would remain involved in some other motor sports, adding: "We have to strike a balance between green cars and a feeling of excitement."