These latest spy shots of the four-door Porsche Panamera are the best yet, revealing in clearer detail than ever the grand tourer’s sleek shape and, for the first time, its plush new interior.

This Panamera’s well-appointed tan leather cabin is clearly visible in our photographs. It’s dominated by a wide and high-set centre console, which should deliver a wrap-around, cosseting sensation that befits a continent-bashing GT.

>> See interior details of the four-door Porsche Panamera

The gear level looks as if it could be a manual, but it’s really a Speedtronic DSG unit with subtle gear selectors on the front of the steering wheel. Porsche seems to be persisting with the controversial back-to-front button shifters, as seen on the latest PDK 911, rather than more traditional paddles.

The flat, centrally mounted navigation screen is set unusually low, but should be a new-generation touch screen system. Most of the system controls are mounted on the imposing centre console, leaving a clutter-free dashboard.

Porsche’s first ever four-door will be launched in the second-half of next year. Autocar’s seen a prototype; in the metal it’s low, sleek, around five-metres long and should have space for two adults in the rear.

The Panamera’s based on the same platform as the Cayenne, and will boast a range of longitudinally mounted engines including a direct-injection V8, a V6 and potentially a diesel V6. It will also become the first Porsche to deliver the company’s new electric-gasoline hybrid system, which will also be fitted to the next generation Cayenne in 2010.

Stuttgart intends to build around 30,000 Panamera’s per year and a starting price of around £50k has been forecast.

Will Powell