Next-generation hatchback gets the brand's latest cabin layout and a funky new LED ambient cabin lighting system.

Photographers have snapped the all-new BMW 1 Series during development testing once again, though this time we're getting a first look at the new-gen model's overhauled cabin.

Compared to the current car, the new 1 Series gets the design and layout of the company's latest range, which should not only see the introduction of BMW OS7.0 incorporating a large central infotainment display and the availability of an all-digital instrument cluster for the first time, but also a much-needed lift in cabin fit and finish.

The steering wheel, instrument binnacle and centre stack have basically been lifted out of the larger 3 Series, which should look and feel much more modern than the model currently on sale.

The trick new ambient lighting system appears to be an evolution of the technique employed in the Mini range – of which the new 1er will share its UKL underpinnings – with cool blue LED patterns adorning the doors and dashboard. We assume various colours will be able to be configured.

It's likely the vehicle seen in the images is the new flagship performance variant, likely to be called the M135i xDrive, which should get a high-output 2.0-litre turbocharged petrol engine and all-wheel drive.

Given the new X2 M35i xDrive manages a 4.9-second sprint to 100km/h with its 225kW/450Nm turbocharged four-pot mill, expect the 1 Series to achieve mid-fours with the same drivetrain.

That's rather close to the current rear-driven M140i, which claims a 4.6-second run to triple figures with the eight-speed automatic transmission. It's worth noting the current model is powered by a much larger 3.0-litre turbocharged inline six making a healthy 250kW and 500Nm.

While many will lament the shift from rear-wheel drive to front, the new platform should free up more space in the rear, improving accommodation for rear occupants as well as the boot.

It's believed the all-new 1er will make its public debut at the Frankfurt motor show in September, so stay tuned to CarAdvice for all the latest in the lead-up.

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