Williams-Renault, Benetton-Ford, Ferrari and Sauber all faced the possibility of sanctions when the world council met in Paris to examine a report by Fisa's technical delegate and evidence from the teams. The authority concluded it had no absolute proof the fuel was illegal.
The world council said: 'The information and explanations offered by the competitors concerned and by the eminent experts from the relevant fuel suppliers have cast doubt on the accuracy of the tests which formed the basis of the technical delegates' reports. The benefit of any doubt must always be given to the competitor. Accordingly we confirm that the results of the grands prix of San Marino, Spain, Monaco and Canada stand.'
Teams were warned, however, that in future they must provide fuel samples for approval before races.
Jaguar were disqualified yesterday from their GT-class win in last month's Le Mans 24-hour race because of an alleged breach of the rules governing turbo-charged cars.Reuse content