BMW Concept X4 (2013) first pictures of baby X6 coupe-SUV

This is the BMW Concept X4, which borrows the idea of an SUV with coupe proportions from its X6 brother, and shrinks the template down to the size of an X3.

But don't be fooled by the 'Concept' tag of this car – like the Concept 4-series coupe we saw in 2012, the X4 is very much confirmed for production, and will receive only detail styling tweaks before it goes on sale in mid-2014. It'll be built alongside the X3, X5 and X6 models at BMW's Spartanburg factory in the USA from early 2014.

Yes, though that recipe never did the X5-based X6 any harm. 'X' models now make up a quarter of BMW's annual sales, with the X6 consistently performing strongly (especially in the US and Australian markets). The X4, says BMW, is a 'Sports Activity Coupe' meaning it has a more a steeply raked, lower roofline than its boxier X3 sibling. At 1622mm tall, the Concept X4 stands 53mm lower than the X3, and 34mm wider. This concept model rides on 21in alloy wheels.

The headlights are all-LED units, and use the same light-strip motif as the Concept 4-series. The lights merge with the edges of the XXL-sized kidney grilles (like the new 3-series) and there's a reworked version of the X6's front bumper, complete with a bluff skid-plate.

The car's flanks are dominated by those two sweeping styling lines, which meet over the rear wheel to emphasise 'forward surging momentum', or so says BMW. The raked roofline and short overhangs are all supposed to point towards the X4's sporty brief. Tell us if you like the results by clicking 'Add your comment' below.

At the rear, there's another chromed skid-plate apron, but here it's made to look like a racey diffuser. The lights again recall the 4-series concept, as do the extrovert exhaust surrounds. Expect the sculpted rear bumper treatment to be toned down for showroom-ready X4s; the 4-series did the same, as revealed in these spy shots.

No shots of the X4's cabin have been released, but it's likely to closely resemble the X3's interior. BMW has confirmed the Concept X4 uses its xDrive all-wheel drive system, but is keeping quiet about the powerplanst.

But production X4s will use familiar BMW four- and six-cylinder petrol or diesel engines, and offer a choice of xDrive or rear-drive sDrive set-ups, with either six-speed manual or eight-speed automatic transmissions.

We hear there won't be a two-door model (despite this being a Sports Activity Coupe) and the rumoured X4M apparently isn't on the cards either, as there's no X3M. But BMW's new M Performance brand (a halfway house between its regular models and the full-fat M cars) is considering an X4 M40i and M40d. These two petrol and diesel X4s would use twin-turbo 3.0-litre straight-six engines, good for an identical 340bhp.

Expect the X4 to carry a £2k premium over the X3, so prices will start at around £31,000 when sales commence in the middle of 2014.

By Ollie Kew