Audi has launched the brand new A7 Sportback amid a river of champagne (and miniscule canapés) at a packed Pinakothek der Moderne München.

The new five-door coupé is to the Audi A8 what the A5 Sportback is to the A4; it combines the A8's space and general air of luxuriousness with coupé-like styling and five-door hatchback practicality.

The A7 cognomen cleverly pitches the coupé above the Mercedes-Benz CLS and BMW 5 Series GT - both based on cars in a lower class than the A8 - though they're its most obvious rivals at the moment.

Introducing the newcomer, Audi chief Rupert Stadler said: "It's more than just pure beauty. It's got a great significance. It will close the gap between the Audi A6 and the flagship A8 - a completely new segment.

"It's not only the most beautiful four-door coupé [sic] worldwide, it's also practical. It is unmistakeable. It is simply breathtaking"

Beneath the surface of a relentless lyrical waxing, Audi unfurled a ream of information on the luxury coupé.

Longer than the Mercedes CLS but shorter than a 5-Series GT, the A7 aims to seat four adults in comfort, and its 525-litre boot is bigger than the A8's.

The electric power steering is a new system, lowering consumption by three percent. One fifth of the bodywork is aluminium, saving weight and, again, abating the big coupé's thirst.

Four engines will be available initially, two petrol and two diesel. None will emit more than 191g/km of CO₂, which is astonishing given the car's general grandiosity.

Petrol power comes from a 2.8-litre - with 201bhp, 207lb.ft and 189g/km - and a 3.0-litre TFSI with 296bhp and 325lb.ft. That one's the quickest, sprinting to 62mph in 5.6 seconds yet emitting just 191g/km.

The diesels options are a 3.0-litre TDI with 201bhp, 295lb.ft and front-wheel drive or a quattro version of the same capacity, with 242bhp and 369lb.ft. They emit 139- and 164g/km respectively.

All engines feature start-stop technology, and even the most profligate 3.0-litre TFSI returns 35.2mpg on the combined cycle. Owners of the 201bhp 3.0-litre TDI model will enjoy 53.3mpg economy.

Prices in the UK start at £43,745 for the front-wheel drive 3.0-litre TDI, rising to £48,060 for the 3.0-litre TFSI quattro. Standard SE specification is generous, including heated leather seats, satellite navigation, DAB digital radio, a powered tailgate, four-zone climate control, a rear parking camera and a head-up display.

Pay for S-Line spec and Audi will add an inch to your wheels, a body kit and a sportier interior. Lowered sports suspension is a no-cost option.

The A7 Sportback hits the shops in January 2011, and those prices include the 20% VAT rate due in the New Year.