At the International court of Appeal in Paris, the FIA has accused BAR-Honda of "fraudulent conduct", in its attempt to bend the rules and deceive its own race stewards.

The FIA claims that BAR "in designing a fuel system calculated to deceive the scrutineers into thinking the car had been drained of fuel when in fact it had not", was "guilty of fraudulent conduct".

Earlier, the FIA's technical delegate, Jo Bauer, admitted that the sport's governing body had known of the 'secret' fuel tank at the time of the Malaysian Grand Prix.

"We did a general inspection of all fuel cells of all teams," he admitted, when giving evidence, "following a request made in the Technical Working Group on February 4th to check that the right material is used. We also checked the extremities of the fuel cell and the regulation concerning the size of the fuel cell.

"The thought was that, if we had to drain fuel, we would have to have a closer look to see if there was fuel in it or not."

It's thought that the case could rest, not so much on the fact that there was a 'secret' tank, but the reply given by members of the BAR team at Imola once Jenson Button's car had (apparently) been drained of fuel. Asked if the car was now fully drained, a team member said "yes". Following this, the 'secret' tank and its contents were discovered.

BAR vehemently denies any wrongdoing, however it has urged the FIA for clarification of the rules in order that there is no doubt in future. Talking to reporters outside the court, Fry said: "Our lawyer pointed out very clearly that in other FIA championships, like sports cars and touring car racing, there is a very clear definition of what you have to do at the end of a race and what a pump out of the total fuel system is. Those rules don't exist in F1."

In court, BAR's QC, David Pannick, urged that should his client be found guilty, a "modest" fine, rather than exclusion from the championship, would be appropriate.

"In our submission we ask you to reject any case of fraud, bad faith or deception as not having been proven by the FIA. We say you should also find in our favour of the proper interpretation of the rules," he said.

"If you were to be against us," he continued, "my submission would be that a fine would be to suffice because we have produced data that without this extra fuel then the car could not have got around the track. In those circumstances a modest fine would be sufficient."

The FIA however, is pushing for exclusion, a move which to many would be unthinkable. However, before the season had even begun, Max Mosley had warned that any team caught cheating would be excluded, and to go against that would cause both he and the FIA serious loss of face.

Furthermore it would send out the wrong message to the other nine teams, one or two of which are believed to have 'tipped off' the FIA in the first place.