Japanese automotive giant Mazda is on the brink of achieving a world first with the introduction of its street legal, hydrogen-powered rotary engine car to Japan's roads.

The specially adapted, eco-friendly Mazda RX-8 sports coupe has been undergoing tests on Japan's roads after the country's transport authorities recently gave permission to trial the zero-emission vehicle.

The Ministry of Land Infrastructure and Transport's (MLIT) decision to permit the tests comes just one year after Mazda first showcased the rotary engine technology at the 2003 Tokyo Motor Show.

Mazda's long-term goal through the tests is to have the eco-friendly vehicles available to lease to governments and fleet users within two years.

The adapted RX-8 is powered by a modified version of Mazda's award-winning RENESIS rotary engine that features an electronically controlled hydrogen gas direct injection system on the rotor housing.

The invention marks the latest step in the path towards the 'hydrogen economy', with the fuel cell industry continuing to mature and the necessary infrastructure for a hydrogen-based transport network slowly emerging in countries such as the US and Japan.