The S500 PLUG-IN HYBRID is the brand’s first European model to feature technology which will be available on the new C-Class from next year.

In the S-Class, this combines a 3.0-litre V6 petrol engine with an 114bhp electric motor, producing a combined 437hp and offering a 4.2-second sprint to 62mph. It takes around four hours to charge the lithium-ion battery, which in turn offers a 20-mile electric range at up to 87mph.

With or without charge in the battery, the S500 PLUG-IN HYBRID features the same Intelligent Hybrid system as its conventional hybrid siblings. This maps the topography of the road ahead and automatically selects the most efficient use of electric and petrol power based on available regeneration opportunities. It can also decouple the engine when under low loads.

The result is a combined fuel economy figure of 101mpg on the NEDC test, corresponding to 65g/km CO2 emissions which will class it as an ultra-low emission vehicle in the UK and allow it to qualify for London Congestion Charge exemption. Hybrid components are warrantied for six years or up to 62,000 miles.

Likely to be a popular car with chauffeur fleets in the UK, the S500 PLUG-IN HYBRID is only available with a long wheelbase and comes equipped with all-LED lights, the full driving assistance package with semi-autonomous driving in traffic jams, fully adjustable front and rear seats, a panoramic sunroof and Burmester sound system.

Prices and specification for the UK are due to be announced in the coming weeks, ahead of first deliveries expected at the end of the year.