The Audi A1 and the Volkswagen Polo share the same PQ25 platform, although Audi has modified the platform to accommodate an all-wheel drive system for the upcoming new Audi A1 quattro. It seems it would be quite easy for Volkswagen to adopt that same platform for a possible Volkswagen Polo R. But there's more to it than that.
A Volkswagen R insider recently told Autocar in the UK that placing a Polo R within the Volkswagen range would be quite difficult, in terms of its price. The insider said that a Polo R would have to be slotted somewhere in between the Polo GTI and the Volkswagen Golf GTI, a gap that is relatively small (around $10,000).
So although the demand for a Volkswagen Polo R might be present, Volkswagen would find it too difficult to market the car alongside two of its hottest small hatches. It's a bit of a bummer really as a small all-wheel drive hatch would be a cracker of a car as a cheaper alternative to the upcoming Audi A1 quattro.