BMW's Rolls-Royce Motor Cars has released more details of its next new and smaller model, the RR4, due to be launched in 2010.

The automaker, which has publicly talked about the new car before, said on Tuesday (27 May) the RR4 would be smaller than Phantom and powered by a unique new engine - the Phantom's V12 is shared with parent BMW.

Rolls-Royce added that the design was signed off in 2007 and engineering development is now fully under way.

Its Goodwood manufacturing facilities also are being completely reconfigured to accommodate the new line, with extended paint, wood and leather shops as well as a second assembly line. The company will move to a two shift system next year as it gears up for full production of the new car.

Chief designer, Ian Cameron, said: "The RR4 has a more informal presence than the Phantom models with a greater emphasis on driving. In design terms this is expressed through its slightly smaller dimensions... It is a true and uncompromising Rolls-Royce in every sense."

"RR4 will mark a milestone in the history of Rolls-Royce Motor Cars," chairman Ian Robertson added. "The business continues to go from strength to strength and the introduction of this new model will expand the appeal of the brand. We look forward to this next chapter with anticipation and confidence."

Further design and engineering details will be announced during the course of 2009, the automaker promised.