The new Audi S1 and S1 Sportback have been officially unveiled, with the company describing them as the first sub-compact production cars to use four wheel-drive.

Power comes from a new 2.0-litre TFSI four-cylinder petrol engine that develops 231PS and 370Nm of torque.

Mated to a short-throw six-speed manual gearbox, the Audi S1 can accelerate from 0-62mph in 5.8 seconds, its five-door Sportback brother only marginally slower at 5.9 seconds.

Top speed for both models is an electronically-limited 155mph.

The S1 is said to record 40.3mpg on the combined cycle, with the Sportback achieving 39.8mpg.  CO2 emissions are 162 and 166 g/km respectively.

Both models transmit their power to the road through Audi’s quattro four-wheel-drive system.  It uses a hydraulic multi-plate clutch in the rear axle to distribute torque as necessary, its responses governed by a function of the electronic stability control module which can also apply braking force to the inside wheel during cornering to ensure stability.

Although based on the Audi A1, the company says the suspension has been extensively reworked, with new pivot bearings at the front and a four-link set-up that replaces the torsion beam rear suspension of the A1.

Larger 310mm front brake discs with an upgraded master cylinder take care of braking duties.  Standard wheels are 17-inch, with 18s available as an option.

Standard equipment also includes xenon headlights, part-leather sports seats, and a six-speaker stereo system with 6.5-inch retractable display.

Two new colours are exclusively available – Vegas Yellow and Sepang Blue.

The new Audi S1 will be available from mid-March priced from £24,900, with the five-door S1 Sportback at £25,630.