The RAC told drivers to come to a safe stop and not continue driving if a red battery warning light appears on the dashboard. The alert comes at a rough time as fuel costs climb sharply. The price to fill a diesel family car now hits a grim threshold per tank. Oil prices have turned around and risen back above a key level per barrel.

In other motoring news, safety guidance highlighted seven initial warnings of failing brakes. Motorists described swerving potholes as much like a frantic bout of a chaotic karting race.