Toyota hasn't even officially unveiled the GR Yaris, although had the opportunity to drive a prototype. Still, rumours have already started swirling about an even hotter GRMN version. Naohiko Saito, the GR Yaris' chief engineer, referred to the possibility while talking with Motoring from Australia by saying, "In the future, maybe we can." He also tempered expectations by adding the even hotter Yaris was "under consideration."

Gallery: Toyota GR Yaris prototype

Insiders indicate that the GRMN would weigh even less than the already lightweight 1,180 kg (2,600-lb) GR Yaris. According to Saito speaking to Motoring, the company commissioned a feasibility study for a full carbon-fibre body for the GR. Since the new model only received a carbon-fibre-reinforced-plastic roof, the team might have earmarked some of the other carbon components for the GRMN.

In addition, the GR Yaris' 1.6-litre turbocharged three-cylinder would receive an increased output. For reference, the prototype that drove had a claimed output of over 250 bhp (186 kilowatts) and 258 pound-feet (350 Newton-metres) of torque, but the company was clear that these weren't the final specs. 

In terms of chassis revisions, there are reportedly extra braces available as dealer accessories in Japan for the GR Yaris, according to Motoring. These pieces would likely be standard equipment on the GRMN.

The GR Yaris gets an official unveiling at the Tokyo Auto Salon on January 10. Prices reportedly range between €40,000 and €50,000 (£34,300 to £47,200 at current conversion rates). There's also an optional Performance Pack that adds Torsen mechanical self-locking differentials to the front and rear, rather than a single limited-slip unit in the standard version.