Question: When is a Citroen not a Citroen? Answer: When it's a DS...

The French car giant has effectively followed the lead set by Toyota with Lexus and Nissan with Infiniti in hiving off flagship models to form a new prestige brand.

DS - a name taken from the iconic Citroen models from the Fifties and Sixties - was formed 18-months ago, and gradually its stable is growing.

The newest model, out this month, is a facelift of the four-year-old DS 4, a coupe-styled family hatchback which rivals the Audi A3 and BMW 1 Series.

In addition to the regular five-door there's a Crossback version, with slightly raised ride height and go-anywhere looks.

The move acknowledges the trend towards crossover models, which is currently capturing nearly a third of sales in the premium hatchback sector.

Like most rivals, the Crossback remains purely two-wheel drive and its off-road credentials are mainly cosmetic, apart from higher ground clearance and some body-cladding.

Prices of the DS 4, which is based on the Citroen C4, start at £19,495 for the 130 PureTech manual, while the similarly powered Crossback comes in at £21,475.

There is a choice of six engine options ranging from 1.2-litre petrol to 2.0-litre, 180bhp diesel, and shortly there will also be a high performance 210bhp petrol version joining the line up.

Not only does the new DS 4 look more rakish and bolder with its restyled grille, LED headlights and new colour schemes, but it feels sharper and more driver-orientated partly thanks to tweaked suspension.

Pick of the engines for me is the entry level 1.2-litre PureTech. Despite its diminutive size, the tiny three-cylinder turbo kicks out 130bhp and has an eagerness and willingness to rev that will appeal to keen drivers.

More surprising than its crispness though is its refinement and general quietness which eclipses most other small units...no wonder it scooped the International Engine of the Year award.

Together with a light, slick six-speed gearbox and well-damped suspension it feels every inch a premium product.

With a max of 123mph and acceleration of 0-62mph in under 10 seconds, it couples lusty performance with good economy. Combined average is 55.4mpg and CO2 emissions are just 119g/km, keeping tax bills low.

Particularly popular with user-choosers is likely to be the economical 2.0BlueHDI 150 which manages a combined average of 72.4mpg and emissions of just 103g/km.

Top speed is 129mph and 62mph is reached in 8.8sec. About £1,000 more will buy you the 180 version with best-in-class torque, automatic gearbox and emissions of a 115g/km.

In keeping with its upmarket aspirations, the DS 4 has a high class cabin with top grade materials, soft-touch plastics, a robust feel and superbly comfortable seating.

It isn't, however, the roomiest car in its class with rear seat legroom being in noticeably short supply if you have long-legged front seat occupants.

The rear doors handles are cleverly disguised, emphasising the coupe profile. But entry through the doors is relatively narrow. The boot can accommodate 385litres of luggage, which is comparable with rivals.

By 2020 DS plans to have a range of six models including at least one SUV. Certainly the new DS 4 will help pave the way towards establishing the brand.