Ferrari car ruled illegal by FIA

Ferrari's car will change look yet again at the Monaco Grand Prix after aerodynamic additions made in Barcelona were deemed to flout rules. Ferrari mounted wing mirrors to the halo of Sebastian Vettel and Kimi Raikkonen's cars in Spain, but the addition of a winglet above the mirrors has landed them in trouble.

The Scuderia sported a new look at the Circuit de Catalunya, but any boost in aero performance was not enough to prevent Mercedes taking a one-two in both qualifying and the race, extending Lewis Hamilton's lead over Vettel in the standings.

Teams had been permitted to experiment with mounting mirrors on the halo, due to driver complaints that the larger rear wings on modern Formula 1 cars were difficult to see past.

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However, FIA race director Charlie Whiting says Ferrari's design is not in keeping with the guidelines that teams were given.

"It's a liberal interpretation of the word 'mounting'," Whiting told F1's official site. "That's how they become legal, because there is no bodywork allowed in the area in the upper part of that.

"The interpretation hinges on whether we think that's a mounting or not. We somehow think not so we're going to take some action on that.

"They think it [the winglet] contributes to the rigidity of the mirror. It's just a matter of interpretation and such a tenuous interpretation is not something we're happy with."

Asked if the device is, in-effect, banned, Whiting said: "Yes, you could say that. If it was a clear breach of the regulations, they wouldn't have been allowed to use it [in Barcelona]. But we'll clarify that to everybody.

"If we do [see it used in Monaco] we're probably going to see the stewards about it. The technical directive will make it clear.

"I doubt they would be there if there wasn't a measurable aero advantage, but these days that doesn't have to be big."