TECHNICAL upgrades have resulted in Citroen's flagship DS5 model becoming more efficient and environmentally considerate than before.

It means all three Hybrid4 200 Airdream EGS6 models in the line-up deliver CO emissions from just 91g/km, along with improved fuel economy.

New management software has been developed for the full-hybrid diesel powertrain with enhancements like improved energy recovery when decelerating and braking, and a new battery management system.

So the DS5 Hybrid4 drivetrain reduces the official CO emissions for the DSign model from 99g/km to 91g/km, while DStyle and DSport versions see their emissions cut from 107g/km to 102g/km.

And 17-inch ‘Houston' alloy wheels are now available as a no-cost option on Hybrid4 DStyle and DSport versions, reducing the cars' emissions from 102g/km to 91g/km - the same as the entry-level DSign.

Prices are from £27,600 for the Citroen DS5 DSign Hybrid4 200 Airdream model rising to £32,200 for the DSport version.