BMW has launched a six-cylinder 1-series - the 130i - powered by the world's lightest six-cylinder petrol engine.

First seen in the 630i, the new engine develops 258bhp and 300Nm of torque to deliver claimed class-leading performance figures.

The three-litre straight-six petrol engine powers the new variant from zero to 62mph (100km/h) in 6.2 seconds and on to a electronically-limited top speed of 155mph. BMW said this is better than rivals such as the Alfa Romeo 147 GTA, Audi A3 3.2 V6 Sport Quattro Sportback and the Mercedes C320 SE Sports Coupé.

The car posts 31.4mpg on the European combined cycle test.

Power goes to the rear wheels via a standard six-speed manual gearbox.

The six has chrome kidney grille slats, 17-inch alloy wheels and large twin chrome exhaust pipes.

Standard interior trim includes sports seats, leather steering wheel, 'business' radio with single CD player and six airbags. BMW's active steering system will be optional.

The 130i debuts at the Geneva Motor Show in March, goes on sale across Europe in the summer and reaches the UK and other right-hand drive markets next autumn.