Spy shot Peugeot 407

And that's unlikely to change if the 407's replacement - the 408 heavily camouflaged in these images captured by Carparazzi - is simply an evolution, rather than the huge step in styling that saw the progression from 406 to 407.

A Peugeot insider says the body will have eye-catching detailing and 'hard-edged' cues, but the differences will be subtle. "The car will be an evolution, not revolution," said the source.

However Peugeot is not hanging back when it comes to powertrain changes across its ranges, and while there are few details about the engines to be offered, you can be fairly sure the new 408 will feature a hybrid drivetrain in the line-up, most likely with a diesel engine rather than the more usual petrol.

The French carmaker is pioneering the diesel hybrid in cars like the 3008 and will extend the technology to its next generation of sedans.  A hybrid 408 should be capable of class-leading economy and CO2 of less than 100g/km.

The 408 is expected to use the same platform as the Citroen C5, and could include high-end safety features such as a heads-up display and adaptive headlights. It is expected to be officially revealed and go on sale in 2010.