Japan's transport ministry may review and improve its car recall system, reports said Sunday, as Toyota Motor Corp. battles accusations it may have delayed acting on drivers' complaints.

The step reflects deepening concerns in Japan over Toyota's recalls of more than 8 million vehicles, most of them in overseas markets.

Transport Minister Seiji Maehara told Japanese lawmakers Friday that he hopes to try to improve his agency's recall system to respond better to consumer interests, Kyodo News agency reported.

"We will consider reviewing the recall system to make it more familiar to users," Maehara told a lower house committee.

The agency may require automakers to move more quickly to fix defects and may expand the types of problems subject to reporting requirements, according to the reports, which also included one in the Yomiuri Shimbun newspaper. The reports cited unnamed ministry officials.

Calls to the ministry rang unanswered Sunday.

Toyota's president, Akio Toyoda, is to appear Wednesday before the U.S. House of Representatives Oversight and Government Reform Committee. Its chairman, Rep. Edolphus Towns, a Democrat from New York, virtually compelled Toyoda to attend last week after issuing a formal invitation for him to testify.

Toyota has not given any details of Toyoda's travel plans, though the Japanese newspapers Yomiuri Shimbun and Mainichi Shimbun reported he left Japan over the weekend.

Maehara and other Japanese officials have applauded Toyoda's decision to attend the hearing and voiced their support, saying he should use the opportunity to reassure customers angered by recalls over sticking gas pedals, accelerators jamming in floor mats and momentarily unresponsive brakes.

U.S. safety regulators are also investigating complaints about power steering in the Corolla, Toyota's top-selling model worldwide, with 1.3 million sold last year. The estimated 500,000 Corollas in question in the U.S. market are not made or sold in Japan.

As Toyota wallows in its recall mess, there has been relatively little talk here about how and why its famously impeccable quality control regime failed — and why mainly in overseas markets.

But a review by the transport ministry could focus on such issues inside Japan, where the company has recalled about 223,000 Prius hybrid cars for braking problems.

The number of complaints over quality and safety issues in the U.S. has dwarfed those in Japan, largely because the millions of Toyota vehicles subject to recalls were made with parts not used in models made and sold in Japan.

The recalls crisis has raised doubts over the Japanese automaker's sterling reputation, earned over decades of striving to win over American and European drivers.

Even Toyoda, grandson of the company's founder, has publicly lamented the difficulties of keeping a grip on quality in an era of outsourcing and global expansion.

"We so aggressively pursued numbers that we were unable to keep up with training staff to oversee quality," he told reporters at a news conference in Tokyo last week.

Toyoda has promised an outside review of company operations, better responses to customer complaints and improved communication with U.S. federal officials.

Japan, where the customer is said to be "king," has had plenty of product quality crises — some of the most notorious involving automobiles. And the transport ministry, similar to the National Highway Traffic Safety Administration in the United States, does keep public records of recalls and drivers' complaints.

But Japanese citizens tend to be less assertive, partly because the legal system and other government institutions are more likely to side with manufacturers than with consumers. Back home, Toyota's travails are drawing attention, but not the sort of outraged criticism seen in the U.S.

"Americans are whinier. But it's also that most Japanese are aware that, at the end of the day, the consumer hasn't come out satisfied and mollified and compensated," says Jeff Kingston, director of Asian studies at Temple University in Tokyo.

Still, if the problems expand back in its home market, Toyota is bound to face some high-stakes questions here, too.

Japan's biggest recent auto quality case involved Mitsubishi Motors Corp. and its truck unit, which were mired in a scandal that first surfaced in 2000 over systematic hiding of defects for decades. The automaker recalled millions of vehicles — some models repeatedly for multiple problems.

Although the manufacturer has promised the cover-ups will never happen again, it acknowledged in 2004 that it didn't come totally clean in 2000.

Two former Mitsubishi Motors employees were convicted of professional negligence in a 2002 accident in which a housewife was killed and her two young sons injured when a wheel flew off the axle of a Mitsubishi truck.

Parts that connected the wheel to the truck were among the defects requiring recalls, which also included braking systems.

A former Mitsubishi Motors president, Katsuhiko Kawasoe, was convicted of the same crime in a separate 2002 accident in which a driver died when the brakes of his Mitsubishi vehicle failed.

"Many automakers viewed Mitsubishi's problem as a wakeup call. Before, the problems were not handled so vigorously," said Christopher Richter, an auto analyst at CLSA Asia Pacific Markets in Tokyo.

"Mitsubishi Motors never recovered from that," he said.