Mercedes considers BMW X6 rival

* New model to be built at US factory * Niche model possibly due in 2013 * More details expected at Detroit motor show...

Mercedes considers BMW X6 rival

Mercedes is expected to add a four-door SUV to its line-up to rival cars such as BMW's X6 4x4 coupe.

The company has revealed that an all-new model will be built at its US base in Alabama, and that it has invested $350m (around 220m) in the factory to prepare for production.

No official announcement has been made, but Mercedes sources have hinted that a new SUV is on the way.

This is despite figures showing that BMW's X6 has recorded sales of just 6087 cars since it was launched in September 2008.

A Mercedes spokesman confirmed that any new model would not be released before 2013 at the earliest.

Further information is expected at the Detroit motor show in January.