The Levorg concept, named by combining the words Legacy, Revolution and Touring, made its debut at the Tokyo show.

It was shown with two types of powertrain; the first was a new horizontally opposed 1.6-litre direct-injection turbocharged petrol boxer engine, the other a similar unit displacing 2 litres.

Subaru claims that both have the power to make "driving smooth and lively", and that the engines offer "superb driving pleasure and extraordinary environmental performance".

Both transmit drive to the road through Subaru's Lineartronic CVT (or Sport Lineartronic in the case of the 2.0-litre engine) and familiar all-wheel-drive powertrain.

The 1.6-litre engine is claimed to output 168bhp and 175lb ft, while its claimed average economy is 49mpg. Subaru states that, with this engine, a full tank of fuel will allow owners to cover over 620 miles at an average speed of 62mph.

The 2.0-litre is notably more powerful, producing 296bhp and 295lb ft, but predictably it's less economical, with a claimed average of 37mpg.

Modern equipment in the Levorg includes 'Eyesight', a lane keeping assistance system that can control the steering, a feature that prevents excessive unintended acceleration in reverse, hazard avoidance and adaptive cruise control.

Numerous safety features are also fitted, ranging from an emergency stop signal to warn drivers of rapid deceleration, to multiple airbags and the use of high-tensile steel in the Subaru's structure.

Fuji Heavy Industries President Yasuyuki Yoshinaga said: "The Levorg is the culmination of all our know-how developed in recent years. It combines the best of our knowledge with new technology and high-performance turbo engines."

Subaru claims that the Levorg will deliver a comfortable and roomy interior, while high-quality finishes and detailing have reputedly been employed to deliver an overall premium feel.

The company says the model will "merge driving, safety and environmental friendliness at an exceptional level", and that the goal of the Levorg is to make every customer who owns this vehicle thoroughly satisfied with it".

A production version of the Levorg is already in the works, says the firm, and will be launched in Japan in Spring 2014.