Mercedes will launch a plug-in hybrid version of its C-class sedan in the international markets in 2015. Mercedes sources have confirmed to Autocar UK that, rather than running a six-cylinder petrol engine as originally expected, the car will use the 208bhp 2.0-litre turbocharged petrol engine from the C250 as an engine-generator.

Electric power will come from a 67bhp electric motor, drawing power from a battery pack. The C350 Plug-in Hybrid will be offered in sedan form only, and is primarily intended for the Chinese and North American markets. "It will be an expensive car," one Mercedes source advised, "more expensive than a C400 petrol, probably."

The plug-in hybrid can be distinguished by a flap, mounted in the rear bumper that allows owners to access the car's charging connector. Other changes include the addition of an 'active' grille shutter, which can close to reduce drag and cut warm-up times. The Mercedes' interior remains seemingly unchanged but buyers can expect new menus and readouts in the COMAND media system for the car's drivetrain and battery.