A general view shows the main entrance of the Toyota Motor Corp Tsutsumi Plant, the production venue of Prius hybrid vehicles, in Toyota, Japan's Aichi Prefecture. Photo: AFP

Toyota's handling of a dangerous gas pedal defect came under fresh scrutiny Monday after the group said it had fixed the flaw for some cars in Europe last year but initially decided against a global recall.

Toyota's woes are set to deepen this week when the world's largest auto maker is expected to pull as many as 300,000 Prius hybrid vehicles because of a separate issue with the braking system.

The brake trouble comes on top of recalls of more than eight million vehicles worldwide due to sticking accelerator pedals that have severely tarnished the Japanese giant's reputation for reliability.

The company, whose brand has long been synonymous with safety and quality, faces a class-action lawsuit on behalf of owners in the United States alleging that it hid problems that have led to the rash of recalls.

And Toyota's North America president, Yoshimi Inaba, is set to testify at a US congressional hearing on Wednesday as part of a wider probe by lawmakers.

Toyota has denied it was slow to respond to the unintended acceleration issue but faces new questions about its handling of the episode, after it emerged that the company acted on the problem in Europe about six months ago.

"We did fix this in August last year (in Europe) after first hearing about the issue at the end of 2008," said Toyota spokesman Paul Nolasco.

But it was initially thought that the problem only affected European right-hand drive vehicles, sold mainly in Britain and Ireland, he said.

The trouble was attributed to the car heater blowing hot air on the gas pedal, causing condensation to build up inside and result in sticking, but was not thought to occur in left-hand drive models, he said.

Toyota officials could not immediately confirm whether any action was taken at that point for vehicles already on the road in Europe.

Toyota has come under fire after saying it had fixed the brake system flaw during production of the latest Prius model last month, without warning drivers of those vehicles already on the road.

Toyota is believed to have already notified its dealers in Japan that it will pull all the new model Prius vehicles sold in Japan, in a recall that is also expected to affect the United States, Europe, China and other markets.

The company is also expected to begin recalling its Sai and Lexus HS250h hybrids, which use the same braking system as the Prius, by the end of this month, the Nikkei business daily reported.

The Prius -- which combines a petrol combustion engine with a battery-powered electric motor -- is Toyota's flagship hybrid car and key to its efforts to stay in pole position in fuel-efficient vehicles.

Toyota, which in 2008 dethroned General Motors as the world's biggest car maker, has seen its brand image badly hurt by its handling of recalls affecting more than its entire 2009 global sales of 7.8 million vehicles.

The accelerator problems have been blamed for several accidents, including one in California in August in which four family members were killed.

Company president Akio Toyoda said Friday he was "deeply sorry" for the string of quality issues and said he would head a new task force to raise standards and investigate the cause of the problems.

Toyota shares fell 1.05 percent to 3,280 yen on Monday, having plunged by more than 20 percent in roughly two weeks.

Toyota has said it expects the accelerator trouble to burn a two-billion-dollar hole in its profits this year in recall costs and lost sales.