Toyota has shown off a mid-engined version of the GR Yaris, hinting at a radical new development of its acclaimed hot hatch – or a future mid-engined sports car.

Named the GR Yaris M Concept, it swaps the GR Yaris's front-mounted 1.6-litre turbo triple for a new 2.0-litre turbo four mounted behind its rear seats.

This appears to be the new powerplant developed by Toyota as part of a deal with compatriots Mazda and Subaru, of which technical details remain under wraps.

Outputs are said to range from around 400bhp in road-going specification to 600bhp-plus in racing guise. 

Power is sent through all four wheels and up to half of it can be transmitted to the front.

Toyota said it would enter the M Concept into Japan’s Super Taikyu racing series to stress-test the prototype engine “to failure”.

It will take feedback from drivers in the process, including company chairman Akio Toyoda’s racing alter ego, Driver Morizo.

This suggests that the M Concept may not hint at a further development of the GR Yaris but something altogether different. It's possible that it's actually a test mule for the long-mooted MR2 revival, which was reportedly green-lit for production last May.

Notably, the GR Yaris has a similar wheelbase to previous MR2s, at 2560mm: the Mk3 measured 2450mm from axle to axle, the Mk2 2400mm and the Mk1 2320mm.

It stands to reason that a modern interpretation of the famed mid-engined roadster would be a larger car than its forebears, bringing it closer to the GR Yaris in size.

Toyota hasn't confirmed anything to this end, however.

So far, the biggest hint the company has dropped concerning a new MR2 came from its promotional cartoon series, Grip. A recent episode briefly showed a whiteboard containing a list of new models: Mk6 Supra, Mk8 Celica, Mk4 MR2, Mk3 GR86 and GR GT3.

Since then, Toyota’s vice-president has confirmed that work has begun on the next Celica, suggesting the other models listed could well be on their way too.