BMW is working on the higher-performance M35i versions of the X1 and X2. These two spy videos catch their development at the Nürburgring.

The latest X1 already debuted, but it's currently available with a 2.0-litre turbocharged four-cylinder that makes 241 bhp and 295 pound-feet of torque. The M35i will reportedly have a higher-output 2.0-litre turbo with an output estimated to be between 302 bhp and 315 bhp. This model will have all-wheel drive.

Compared to the existing X1, the M35i version boasts a more aggressive front fascia with diagonal uprights on the outer portions and a subtle splitter. At the back, there's a boxy bumper, quad exhaust pipes, and tiny strakes on the diffuser.

The styling recipe is similar for the X2 M35i, but the pieces have a different design. The front fascia has a blockier appearance than the X1. There's a ducktail spoiler on the rear deck. Quad exhaust pipes are below the bumper.

Judging from spy shots, the X2 has an interior layout that's very similar to the current X1. The instrument cluster and infotainment screens share a single bezel on the dashboard. The centre stack includes HVAC vents and a large spot for holding a phone. The design keeps the physical buttons to a minimum. Presumably, the M35i versions would likely receive some sporty trim like bits of carbon fibre or aluminium. 

We have no details yet about when the M35i models might arrive, but they should premiere before the end of the year. The new X1 is already on sale in the United Kingdom, so the timing is right to broaden the lineup. 

The X2 hasn't yet debuted. It's not clear whether BMW would launch the M35i at the same time as the lesser trims or bring them out simultaneously.

In terms of pricing, the X1 currently starts at £34,340. Buyers would pay a higher price for the more powerful M35i. The X2 would be even more because BMW generally charges a premium of a few thousand dollars for its coupe crossovers over the boxier versions.