FAST Fords have to be fun and the latest to get the ST treatment is the new Focus which for the first time is coming with diesel power as well as a potent petrol engine.

Dressed to look the part with sporty body kit, mesh grille and prominent spoilers the newcomer is Ford's answer to the likes of the current Golf GTI.

And with Volkswagen now offering a sporty diesel in the shape of the Golf GTD, Ford is following suit and fitting a 185ps, 2.0-litre oil burner in the new Focus ST as well as a feisty 2.0-litre twin turbo petrol engine developing 250ps.

As with the previous ST the fourth generation model is available as a five-door hatch and an estate now priced from £22,195 and topping out at £27,095.

Ford is not charging a premium for the diesel on any of the three Focus ST trim levels and that makes it an attractive proposition for those who want some added economy from their sporty Ford with a claimed 67.3mpg from the 2.0 TDCi model compared to 41.3 to the gallon from the petrol version.

Emissions are also lower at 110g/km compared to a best of 159g/km from the petrol when fitted with stop/start making the diesel cheaper to tax. Without stop/start the petrol engine has a CO2 figure of 169g/km.

It is Ford's flagship diesel and quick off the mark too with a 0 to 60 6ime of 8.3 seconds topping out at 135mph.

With a large amount of mid-range pull it is a brisk mover through the gears yet with a six-speed box will cruise sweetly at motorway speeds with little thirst.

The diesel ST returned close on 40mpg on a brisk run through the mountains just outside Barcelona and although no slouch it is by no means as rapid as its petrol counterpart.

In this guise it sets new standards for a Focus ST rocketing to 60mph in just 6.7 seconds while delivering a healthy roar from the exhausts, now housed in a twin hexagonal cluster in the middle of the rear diffuser.

That is a soundtrack missing from the diesel engine which is generally more down to earth.

With its turbos on song the EcoBoost engine pumps out almost as much torque as the diesel and Ford has deployed a lot of electronics under the skin to keep the power in check.

The torque vectoring system which keeps the car balanced when cornering has been enhanced to deliver more stability and there is sharp feedback from the steering.

It is a great car to drive - intimate, precise and very responsive.

Short-throw gears and plenty of stopping power from uprated brakes inspire confidence and the ST delivers on all fronts.

The traction systems can be moved through three settings for more enthusiastic driving yet left to its own devices this is a Focus like no other and even driven to excel it still managed to return 31mpg.

The ST - it stands for Sports Technologies - is one of three new bandings in the new Ford Performance camp which will include high performance models such as the next Focus RS and the Mustang GT 350R and ultra high performance cars in the shape of the new 600 horsepower GT revealed at this year's Detroit Motor Show.

As part of the ST experience the new Focus comes with body-hugging Recaro sports seats front and rear which, depending on trim come either in full leather or with coloured fabric inserts.

There are also illuminated kick plates while an ST logo lights up in the instrument panel on start up along with a Ford Performance legend that appears in the eight-inch central display screen.

High grade models come with a Sony sound system, sat nav and Ford SYNC2 connectivity system and all feature a trio of additional gauges on top of the dash for oil pressure and temperature and turbo boost.

The cluster of dials is an ST trait and on the new model they sit in a streamlined nacelle angled towards the driver.

It is a suave treatment for the interior. Long gone are the days where the inside of a hot hatch was stripped down to basics.

This is plush and the ST aura can be embellished with some exclusive paint jobs including bright orange, red and a dark grey which Ford is calling Stealth.

At well under £30,000 the Focus ST has to be the leader of the performance pack. It's affordable, sporty fun that is guaranteed to keep the Ford fanbase happy.