Toyota Motor Corp is preparing to recall its iconic Prius hybrid car to address more than 100 complaints about delayed braking, spreading the top automaker's quality woes to one of its most important models.

A source with knowledge of Toyota's discussions with Japanese safety authorities told Reuters on Friday the world's biggest automaker was leaning towards issuing a recall, even if the transport ministry does not technically consider the issue to be a safety hazard.

Toyota, which has earned a reputation as the front-runner in green technology by pioneering the gasoline-electric hybrid system with the first-generation Prius, has sold 311,000 units of the newest version to date, since its launch last May.

In what could be deemed a broader problem with hybrid cars, Ford Motor Co said on Thursday it would roll out a software patch for consumers to address similar problems with braking reported on its Ford Fusion and Mercury Milan models.

Customers have reported a split-second loss in braking power on both brands' hybrid cars when driving over bumpy or slippery roads, when a delay occurs in the switch from the hybrid's regenerative braking system to the traditional brakes.

Ford said it did not notify the public because it did not believe the glitch represented a failure of the brakes.   

In Japan, Toyota's Prius is now the top-selling car, with sales of the latest model reaching around 200,000 units. Another 103,200 have been sold in the United States, where Toyota is also considering a repair.

Toyota said it was also looking into whether the software glitch exists in its other hybrid cars. There have been no complaints so far, a spokeswoman said. -Reuters