Rather than a fully-fledged X4 M model, BMW is instead looking to introduce an M Performance-badged version of the car. The model is likely to launch at next year's Frankfurt motor show, just months after the larger X5 M and X6 M SUVs have gone on sale.
The two test mules caught in these pictures feature camouflage around their lower body elements, as well as more heavy disguises at the rear. Key styling changes over the standard X4 include a blacked-out kidney grille at the front and new twin exhausts at the rear.
Reports suggest the X4 M40i - as the model has been dubbed - will feature a 3.0-litre turbocharged six-cylinder engine for power, producing between 355bhp and 375bhp. That same engine has already been rumoured for use in the upcoming M2, which is due to go on sale at the start of 2016, and is already in use in the X4 xDrive35i.
While official performance and pricing information has yet to be revealed, expect the X4 M Sport to command a significant premium over the £48,995 asked for the current range-topping xDrive35d in M Sport trim.
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