The model is built on a completely new platform that's exclusive to Audi. In terms of size, Audi says it's comparable to the current A6 saloon with a length of 4.97m and width of 1,91m, but also featuring an elegantly tapered coupe roofline.

The model promises executive class interior space for up to four adults, and up to 1,390 litres of luggage capacity via the long tailgate with its standard motorised operation, which also enables the exact opening angle to be set via buttons on the hatch.

Audi promises that the new platform offers impeccable comfort and control thanks to its five link front and trapezoidal link rear suspension system. It can also be specified with a firmer, 10mm lower sport setting or the bespoke S line configuration. An extensively revised version of the Audi adaptive air suspension system with three ride settings will also be offered as an option.

The new A7 Sportback will initially offer a choice of four FSI petrol and TDI engines. The naturally aspirated 204bhp 2.8-litre FSI and supercharged 300bhp 3.0-litre TFSI petrol units will be complemented by two versions of the 3.0-litre TDI in 204bhp and 245bhp forms. Audi says that the 204bhp version will deliver fuel economy of up to 53.3mpg, and CO2 of as little as 139g/km, thanks to the use of new engine load-reducing electromechanical power steering, as well as Audi's multitronic continuously variable automatic transmission, which is fitted as standard to front-wheel-drive versions.

Two specification levels – SE and S line – will be offered in the UK. Standard kit includes xenon headlamps with LED tail lamps, powered tailgate operation, leather upholstery, electric seat adjustment and heating, cruise and parking controls, satellite navigation, the Audi Music Interface (AMI), DAB digital radio and Bluetooth phone preparation.

The model will be priced from £42,925 OTR when order books open on 13 August, with the price rising to £43,745 OTR when the new 20% VAT rate is introduced from 4 January 2011.