TOKYO: Toyota denied on Friday it had covered up safety problems with its cars and said they were safe to drive, as it began to repair some of the millions of vehicles recalled due to faulty accelerators.

Company president Akio Toyoda, in his first press conference on the crisis, said he was "deeply sorry" for the string of quality issues that has tarnished the group's reputation and triggered a class action lawsuit in the United States.

The Japanese automaker, staring at a two-billion-dollar bill from the recall of more than eight million vehicles around the world, was facing "a moment of crisis", admitted Toyoda, scion of the car-producing family.

Hours earlier, Toyota said it had begun repairing gas pedals in the United States, where it faces a lawsuit alleging it knew about the unexpected acceleration issue "for several years" -- a suggestion the company strongly denies. Related article: Toyota knew of problems in 2007: report

"The company never concealed these cases," said vice-president Shinichi Sasaki.

The accelerator problems have been blamed for several accidents, including an incident in California in August in which four family members were killed when their Lexus sedan sped up on a highway and crashed in a ball of flames.

Toyota, which dethroned General Motors in 2008 as the world's biggest automaker, is reeling from a litany of complaints about problems ranging from unintended acceleration to brake failure. Related article: Toyota checking Lexus hybrid brakes

Toyoda said he was "deeply sorry about the inconvenience to customers due to recalls across multiple regions".

"Believe me, Toyota cars are safe," he said, briefly switching from Japanese to English to emphasise the point.

The Japanese giant said it was still deciding whether to recall hundreds of thousands of Prius hybrids owing to a separate flaw in the braking system.

Toyota said Thursday it had redesigned the anti-lock braking system (ABS) -- designed to prevent skidding -- for the latest version of its Prius produced since last month and would soon announce steps for those already on the road. Related article: Green flagship Prius a new headache for Toyota

The Nikkei business daily said that Toyota had decided to recall an estimated 270,000 Prius cars in Japan and the United States to fix a brake problem affecting the newest version of the hybrid.

But Toyoda said the company was still studying how to handle the brake trouble.

"For the Prius cars that are in the hands of customers already, I have instructed that a solution be found as quickly as possible," he said. "Once the decision is made, we will inform the public."

Toyota said earlier its dealers across the United States had already received the parts, information and training needed to fix accelerator pedals, and that repairs had started.

"We're working hard to ensure that our dealers have the resources and support they need to make sure our customers get their cars fixed quickly," said the company's US head, Jim Lentz.

And in Europe, "parts are now on the way, and actual repairs are expected to start at dealers next week," said Toyota spokesman Paul Nolasco.

US authorities Thursday ordered a probe into the problems with the Prius, sales of which are pivotal to Toyota's efforts to recover from a massive financial loss last year.

US President Barack Obama has been briefed on Toyota's safety problems, the White House said, after Transportation Secretary Ray LaHood said Toyota owners should "stop driving" problematic cars and take them to a dealer.

LaHood's comment caused a brief furore and he later retracted the remark.

In Washington, the National Highway Traffic Safety Administration announced a formal probe into the Prius after 124 complaints from consumers about the 2010 model of the world's most popular hybrid.

Related article: Toyota recall raises questions about computerized cars

Toyota has come under heavy fire in the United States for its handling of recalls affecting about eight million vehicles worldwide -- more than its entire 2009 global sales of 7.8 million vehicles.

Japan's foreign minister urged Toyota to quickly deal with the problems, warning of damage to the image of Japan Inc.

"This is a problem for the whole of the Japanese auto industry, as well as about trust in Japanese products," Katsuya Okada said.

Transport Minister Seiji Maehara said the automaker's response to the crisis had "lacked customer focus".

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