Renault has no plans to revamp its new Twingo in a bid to raise its Euro NCAP crash rating from four to five stars and match Fiat's 500, which is one of the few small cars to gain the top safety level.

Jacques Faure, Renault's head of customer specification in the safety department, said: "The Euro NCAP result for new Twingo is consistent with what we expected, no more, no less. On the basis of cost and market targets we designed the car for four stars."

He added: "We decided from the project's beginning, four years go, that the Twingo would be a real car, one which would be affordable and have real quality. We designed a four-star car which incorporates fundamental knowledge from our huge 50-year safety database."

Faure revealed that Renault and Euro NCAP had some "frank discussions about knee protection details and we did not quite agree with their scoring, but that is the name of the game."

Euro NCAP was also unable to provide a rating for the Twingo's child safety system due to the testing organisation's parameters which prevented installing Renault's child seat with the front seats in the standard position.

Faure said: "NCAP requires testing the best-selling variant, which has a rigid rear bench seat. That combined to the requirement that the front seats are in the middle position meant we could not fit our child seat. Most Twingo models feature 60/40 split seats, adjustable forwards and backwards."

He conceded: "It is true that we might be considered second best against Fiat's 500. Only the Mini and the 500 have gained five stars and cars like the Peugeot 107 are on a par with the Twingo. It is a compromise in some ways. We expected we would have a reaction, but we made our choice and were honest and consistent."

The Twingo, which has been on sale in mainland Europe since June, is due to enter the UK market on Friday (September 7) in upmarket Dynamique 1.2 and GT 1.2 turbo forms.

Faure said: "It would have been very expensive and not ideal to re-engineer the car at a late stage. We have fairly precise knowledge of what is happening on the roads in accident terms and while a four-star level may not be as excellent as a five-star vehicle Twingo is fundamentally efficient in real conditions."