Toyota is considering a global recall of eight models including its flagship Lexus LS460 sedan due to possible engine failure, Japanese reports said on Thursday.

Up to about 270,000 cars worldwide, including roughly 90,000 units sold in Japan, could be subject to Toyota's latest recall due to fears that in the worst-case scenario, the engine may stop while the car is running, the sources said.

Apart from the LS460, other Lexus models - LS600h, LS600hL, GS350, GS450h, GS460 and IS350 - and Toyota's Crown will be subject to the latest recalls of the top Japanese automaker, sources told Kyodo News.

Of the eight, the LS460, LS600h and LS600hL had been recalled in May in Japan because of a steering system defect, the sources said.

According to the sources, there are cases in which engines of the models produce an unusual sound or idling becomes unstable because of component defects.

The defect may have been caused by the presence of foreign substances at the manufacturing stage, the sources said.

"The defective engines, whose valve springs are not working properly, may halt in the worst case scenario while driving," Toyota spokesman Hideto Yukawa told news agecy AFP. "The company is preparing for taking market measures as soon as possible."

He did not rule out a recall announcement in the future.

Sources told Kyodo the automaker is discussing measures to address this issue with the Land, Infrastructure, Transport and Tourism Ministry, with the likelihood that Toyota will decide on voluntary repairs and not a mandatory recall.

The LS460, which has a 4,600cc V8 engine, was first released in 2006 and was partially redesigned last autumn.

It was one of four models, including its two hybrid versions, recalled in Japan in late May due to trouble linked to Toyota's variable gear ratio steering system.

Toyota GB, which recently communicated with media on accelerator recalls only via Twitter, said in several 'tweets': "Improperly functioning valve springs have been found in some Lexus 4.6-litre V8 and 3.5-litre V6 engines. [There is a] small possibility that abnormal engine noise or unstable idling may occur. In very rare instances, chance that engine may stop while driving. Toyota is preparing to take some type of field action and [we] will inform our customers promptly." It later issued identical information in an emailed statement.

Last Friday, Toyota announced it would recall a different Lexus model - the Avensis-based 2010 HS250h sold in the United States - over concern it may cause a fuel spill in a collision.

Toyota on Wednesday issued a total of 50,839 recalls in Japan due to faulty airbags and seatbelts in models including Corollas built between 2000 and 2001.

Toyota - and Honda, Nissan and Mitsubishi Motors - will between them recall more than 100,000 vehicles in Japan because of the issue.

The airbags were made by Tokyo-based parts maker Takata. While no injuries have been reported, the transport ministry warned that the airbag inflator in the passenger seat caused shards to fly out when the airbag opened.

Takata also supplies Audi, Daimler, Chrysler, Ford and General Motors.

The faulty seat belts, which fail to buckle up, were built by Tokai Rika, the ministry said.