Mazda has confirmed UK pricing and specifications for Skyactiv-X-powered variants of the new 3.

The 2.0-litre four-cylinder powertrain, which uses the brand's newly developed spark plug-controlled compression ignition technology, can be equipped from £23,555. This starting price applies to both the hatchback variant and the saloon, which will arrive in the UK in October.

The unit will be offered with a manual or automatic gearbox, and is available on four trim lines: entry-level Sport, Sport Lux, GT Sport and range-topping GT Sport Tech, which tops the line-up at a starting price of £29,775 for the hatch and £27,575 for the saloon.

Sport trim comes equipped as standard with rear privacy glass, chrome detailing and a frameless rear view mirror, while Sport Lux adds keyless entry, a reversing camera and heated front seats. Higher up the range, GT Sport is offered with electrically adjustable leather seats, a heated steering wheel and Bose sound system, and top-spec models receive a 360deg camera and additional driver safety aids.

All Skyactiv-X models feature a 7in digital instrument display and Mazda's new 8.8in infotainment central display, but 18 in alloy wheels, black badges and a wider exhaust tailpipe are added beyond Sport trim.

The firm says the new engine combines the performance of a petrol engine with the fuel economy of a diesel.

The unit has been confirmed to deliver 178bhp and 165lb ft of torque, while producing a fuel economy of up to 52.3mpg on the WLTP cycle, with CO2 emissions from 96g/km. The economy and CO2 figures depend on model, wheel size and choice of gearbox.

The powertrain will also include Mazda's M Hybrid system, a 24V mild-hybrid unit that can regain energy under braking.

The new Skyactiv-X engine is the most marked feature of the new 3, given that it has the potential to breathe new life into petrol power amid stricter emissions and efficiency targets. It also promises “superior initial response, powerful torque, faithful linear response and free-revving performance”, says Mazda.