The BMW 3-series GT has been photographed undisguised for the first time. It is thought the car will be unveiled at the Geneva motor show next year.

BMW has already started pilot production of the 3-series GT at its Leipzig production plant. The GT will be the first new 3-series body style to emerge since the short-lived Compact of 1994.

The new five-door liftback is based on a long-wheelbase version of the latest 3-series platform. Exact dimensions are still under wraps but the GT is likely to get a slightly shorter wheelbase than the Chinese market 3-series Li, which adds 110mm to the standard 3-series saloon’s 2810mm measurement.

The same platform structure is expected to be used for the to-be-confirmed 4-series Gran Coupé — another new four-door, 3-series based variant planned for launch in 2015.

Known internally under the codename F34, the 3-series GT follows the form of the 5-series GT, with a higher roofline and broader waistline than existing 3-series models, along with four frameless doors and a heavily angled tailgate.

With a longer wheelbase than its siblings, the upcoming 3-series GT is claimed to boast more rear legroom and load space than both the latest 3-series saloon and Touring models — something BMW suggests will see it appeal to family car buyers.

An optional glass roof is also said to combine with comparatively large windows to give the new car its own distinct cabin ambience, despite sharing most of its interior fittings with other models. Our photos show both standard and M Sport trim.

As with the 5-series GT, the two-piece tailgate opens either porthole-style or in union with the rear window for added versatility.

BMW engineers are also talking up the 3-series GT’s refinement, suggesting the longer wheelbase has allowed scope for a more comfort-orientated approach to its chassis tuning.