BMW has been told not to run an ad for the M4 after watchdogs agreed with a complainant that it encouraged unsafe driving.
The ad mixed shots of a car on a racetrack with those of a car driven 'sedately', BMW said, on a public road.
BMW (UK) said the ad differentiated clearly between the sedate cruising of one M4 on public roads, where the Highway Code was obeyed at all times, and the on-track element.
It said that the road driver was calm and in control, that he did not overtake other traffic, cross white lines, or exceed UK speed limits, and that the roads were clear of other vehicles and pedestrians. BMW stated that the sections of the ad featuring the car on a race track were "clearly differentiated".
The Advertising Standards Authority said in some shots it was unclear which setting was shown, the ad blurred the distinction between track and road.
The ASA ruled the ad must not appear again in its current form. Future ads must not link racetrack and road driving styles in a way that promotes speed or irresponsible driving.