Audi are pushing ahead with plans for an A9 supersedan to challenge the big boys in the likes of the Porsche Panamera and Mercedes-Benz CLS. The A9 will be marketed as a flagship luxury four-door sports coupe based on the A8.

The interesting part about the A9 is that the platform it uses could very well be used to create the production Lamborghini Estoque as well, killing two birds with one really lightweight space frame stone.

The master plan at Audi was always to produce sibling four-door sports coupes to its sedan models, like how the A7 Sportback is to the A6.

Nonetheless, the A9 hasn’t been given the all-clear for take-off yet as a source from Audi tells Autocar, “The project isn’t officially confirmed for production, but work is progressing on the business case, both at an accountancy and engineering level.”

Excellent news then as Audi is considering a platform-sharing process for the A9 that could see the same platform take the Estoque to production as well since Lamborghini is a fellow Volkswagen Group brand.