Max Mosley, the FIA president, confirmed yesterday that McLaren-Mercedes were told after Sunday's Brazilian Grand Prix that David Coulthard's car would be impounded after its disqualification from second place unless the team agreed that the dimensions involved in the rule infringement had been accurately recorded.

However, he denied that there was any impropriety on the part of the sport's governing body. He said that after the furore over the disqualification and reinstatement of the Ferraris in Malaysia last year the FIA had changed its policy over infringements involving technical dimensions.

"After that episode we told all the teams that if there was a dimensional discrepancy at post-race scrutineering they could either agree the accuracy of the figures or surrender their car to be used as evidence at an appeal hearing," he said.

"Last year Ferrari turned up with a jig which they used to prove that their barge-boards (aerodynamic deflectors) conformed with the rules. Clearly there was a possibility that they might not have conformed with the rules when they were fitted to the car, but under the circumstances we had to give them the benefit of the doubt."

Mosley also said that the FIA officials measured Coulthard's McLaren on several occasions, in front of the team's technical director Adrian Newey in Brazil.

McLaren's protest will be heard on Monday at the FIA court of appeal in Paris, where McLaren are almost certain to argue that the appallingly bumpy condition of the straight at Interlagos caused excessive wear to the front-wing end plates and that the car's performance was not improved thereby.

In this, McLaren will follow Ferrari's successful line of argument, that their minor infringement produced no discernible advantage. Coulthard is hoping that the FIA will take a similarly lenient line and that he will go into the San Marino Grand Prix at Imola on April 9th with his six championship points back.

But last year's decision to restore the winner's points to Eddie Irvine and second place to Michael Schumacher bucked a long-established trend in Formula One that those who appeal a stewards' decision are wasting their time and money.