With instances of "misfuelling" having risen significantly in recent years, the carmaker has redesigned the fuel filler neck in A4, A5 and Q5 TDI models to ensure that it cannot accommodate petrol nozzles

The news is expected to be of particular interest to fleets due to the significant cost and time issues involved with sorting out misfuelling issues.

The newly equipped models in the A4, A5 and Q5 family will be joined by further Audi models in the near future as the system is gradually rolled out.