BMW has unveiled the 6-Series Gran Coupe – an amalgamation of a coupe and a saloon designed to rival the Mercedes CLS and Audi A7.

It is 112mm longer than the standard 6-Series coupe and convertible and offers a considerable amount of additional space for rear seat passengers. BMW describes it as a four plus one layout, which signifies the car’s central rear seat – something that most premium four-door coupe rivals lack.

The Gran Coupe is due on sale in the UK in July and will initially be available with two engines – a 320hp six-cylinder petrol known as the 640i and a 313hp turbodiesel 640d.

The latter will be the most appealing to fleets, with 50.4mpg and emissions of 148g/km. It will also be good for 0-62mph in 5.4 seconds and 155mph.

A 650i version will also be available with a 450hp V8 engine, as will a range-topping M6 Gran Coupe, powered by the 560hp V8 engine from the BMW M5.

The seats are mounted slightly higher than those in the standard 6-Series for improved visibility and the boot can accommodate 460 litres of luggage.

Prices will start at £61,380 for the 640i and £63,895 for the 640d.

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