SAO PAULO, Oct 21, 2007 (AFP) - The McLaren Mercedes-Benz Formula One team said Sunday night it was ready to appeal a stewards decision at the Brazilian Grand Prix, keeping alive Briton Lewis Hamilton´s F1 title dream.

The team made the decision following the stewards´ decision not to punish the BMW Sauber and Williams teams for using allegedly irregular fuel during Sunday´s race, won by Ferrari´s Kimi Raikkonen to claim the drivers´ title.

McLaren officials notified the FIA of their intention to appeal the race stewards´ decision not to penalise BMW Sauber and Williams within an hour of the announcement, which had appeared to seal the championship for the Finn.

The stewards decision also meant the original race result was confirmed and that Raikkonen was confirmed as champion.

He won the race and Hamilton, the 22-year-old British rookie who went into the final race with a four-points lead after leading the championship for six months, finished seventh.

That outcome left Raikkonen one point ahead of Hamilton for the season crown, denying the British racer a world championship in his rookie campaign.

Brazilian Grand Prix stewards decided not to take action against BMW Sauber and Williams despite a report from the FIA technical delegate that stated temperatures of fuel samples taken from both cars of each team were outside the regulations.

McLaren´s decision to appeal now leaves the results of the drivers´ world championship in a state of uncertainty.

If the FIA´s International Court of Appeal overturns the stewards´ decision and, more crucially, disqualifies the Williams and BMW Sauber drivers, then McLaren´s Lewis Hamilton will be elevated from seventh to fourth - giving him enough points to beat Raikkonen for the world championship.

The ICA would still need to accept McLaren´s appeal. If that is done, a date would be set for the hearing.

The BMW Sauber and Williams teams were not punished for the fuel temperature discrepancy because the FIA stewards could not prove that their petrol was outside the permitted limit.

A statement issued by the stewards at Interlagos on Sunday night said that they could not say for certain that the fuel in the cars was below the 10-degree maximum limit allowed in the regulations.

The stewards said that there was a discrepancy between the Formula One Management temperature of 37 degrees and that provided by the FIA and team-contracted meteorologists Meteo France, which was a few degrees cooler.

Furthermore, they made it clear that they did not have certain data in their possession that would have helped prove the teams were in breach of the regulations.

In particular, their statement said they lacked: "a precise reading of the temperature of ´fuel on board the car´ which shows fuel at more than 10 degrees centigrade below ambient temperature"; and "a regulation stating in clear terms that for the purposes of Article (6.5.5) the definitive ambient temperature shall be indicated on the FOM timing monitors alone."

The statement added: "In view of the matters referred to above, the stewards consider that not withstanding the presumptions referred to above there must be sufficient doubt as to both the temperature of the fuel actually ´on board the car´ and also as to the true ambient temperature as to render it inappropriate to impose a penalty."