Mercedes-Benz has revealed the new GLS, its biggest and most luxurious SUV.

With a longer wheelbase than its predecessor, the new GLS provides more interior space for seven passengers.

The seats in the third row can also be lowered into the floor to increase the boot space (up to 2400 litres), while the seats in the second row fold flat.

Like the GLE, the GLS features the latest generation of Mercedes-Benz driving assistance systems.

When Active Distance Assist with route-based speed adaptation is activated, the new GLS is able to recognise and respond to tailbacks or slow-moving traffic with the help of information from Live Traffic before the driver becomes aware of the hazard.

When driving in a tailback on the motorway, Active Stop-and-Go Assist is able to perform the tasks of keeping in lane and maintaining the safety distance with a high level of availability at speeds up to around 38mph. Moving off can be automatic up to one minute after coming to a stop.

The GLS is also equipped with the latest generation of the MBUX infotainment system, which uses two 12.3-inch screens.

A number of functions can be controlled using ‘gestures’.

All seats are electrically adjustable as standard and include an easy-entry function. The seats in the third row are suitable for people up to 1.94m tall and are heated for the first time.

Five-zone automatic climate control ensures the third row has its own zone with air vents in the roof.

The switches on the left and right of the load compartment and on the front of the wheel arches on the front-passenger side in the C-pillar area allow the seats in the rear rows to be folded completely flat.

If the Rear Comfort package Plus is ordered it includes a seven-inch Android tablet in its own docking station in the second row's larger luxury centre armrest. The tablet allows control of all the MBUX comfort and entertainment functions from the rear seat rows, such as access to radio, TV, media, phone and web browser.

It is also possible to order luxury seats with lumbar massage function and climate control as an additional option for the Rear Comfort package Plus in the second row.

The MBUX Rear Seat Entertainment System provides two 11.6-inch touchscreens that allow passengers in the second row to enjoy movies or music, use the integrated web browser, or call up and input trip information.

The GLS 400 d is powered by a six-cylinder diesel with 330PS and 700Nm. It has CO2 emissions from 201g/km and meets the latest RDE2 emissions standard.

Part of the development included improved aerodynamics to help reduce fuel consumption and wind noise.

In all variants, the new GLS used a nine-speed automatic transmission. It can split power from 0-100% between the front and rear axles.

Air suspension with adaptive damping is also fitted as standard. This setup uses sensor systems and algorithms to adapt the damping characteristics to the road condition and driving situation in real time.

Prices are yet to be confirmed, but expected to start at more than £72,000 when the car goes on sale towards the end of the year.