BMW has ditched diesel engines and manual gearboxes as part of a new muscular makeover and tech-filled refresh for its 1 Series hatchback.

Marking 20 years since the launch of its best-selling model, the mid-life update, arriving in October, is intended to continue the hatchback's upwards sales trajectory; it roe 64% last year to 22,855 UK registrations.

It also means the 1 Series keeps pace with its Audi A3 Sportback and Volkswagen Golf rivals, both of which received similarly significant restylings earlier this year.

Both of those cars still retain the option of a manual transmission, and the Golf also still offers diesel power. But it's the simplicity of the range that BMW believes will make the 1 Series more appealing that its rivals.

In the UK, BMW now offers the hatch in only three specifications: the 168bhp 120i Sport and 120i M Sport and the 300bhp M135i xDrive – the latter’s four-pot turbo petrol engine dropping 6bhp on its predecessor.

All exclusively send power through a seven-speed automatic gearbox. 

As with the updated BMW 3 Series, diesel models won't be making the crossing from mainland Europe. BMW has suggested this is in part down to hitting increasingly strict emissions regulations.

For the revamped 1 Series, the biggest change is that new face: lowered, slimmed and given a more angular design for a commanding and sporty road presence, the German brand said.

The tooth-like kidney grilles have also gone, replaced by something more akin to the 3 Series.

The new grille gets a touch of modernisation, too, with the design featuring diagonal bars at its edges.

The 120i M Sport and M135 xDrive feature a more simplistic, horizontal, blacked-out grille design.

In comparison, the rear of the 1 Series has had little work done. Bar a new two-part tail-light, a lowered bumper (in a black diffuser-style design on M Sport models) is the biggest change.

These changes have lengthened the car by a modest 42mm to 4361mm. Its other dimensions remain unchanged.

Inside is where most of the work has been done. The headline change is the arrival of the BMW’s 20in Curved Display. Controlled by BMW’s OS 9 software, it incorporates both the digital instrument display and infotainment system. 

The number of physical buttons has been drastically slashed, including those for the climate control. This, as with most of the car's comfort controls, can now be found within the infotainment touchscreen.

Materials inside have also been upgraded, with Alcantara available in M Sport models.

Meanwhile, new seats are said to offer better comfort over longer distances.

Given the line-up has been slimmed to three models and SE entry trim dropped, pricing has inflated by some £2500.

Final figures have yet to be confirmed, but the 1 Series line-up is expected to start at £31,000 for the 120i Sport and top out at £42,000 for the M135i xDrive.