Tyre company Michelin could pull out of Formula One at the end of next year if the governing body presses ahead with plans for a sole supplier, company chairman Edouard Michelin warned on Saturday.

Michelin told a Belgian Grand Prix news conference that he wanted clarification from the governing International Automobile Federation (FIA) about the reasoning behind the proposals.

"Should a control tyre (single supplier) be adopted for 2008, Michelin would seriously consider withdrawing from Formula One competition," he said.

"Not because we are worried about the outcome of the call for tenders, provided of course that the decision-making process is sound and based on the technical feature of tyres, but mainly because such a situation would simply negate the spirit of racing," he said.

At present, Michelin supply seven of the 10 teams and Bridgestone the rest. Next year, they will have five teams each with Williams and Toyota leaving Michelin.

Michelin said the company's withdrawal could even come at the end of next year.

"So we could withdraw from Formula One in 2008. What about before that, I mean in 2007? We will consider it very carefully and we will discuss the situation with our partner teams," he declared.

Michelin was scathing about the governing body.

LIMITED TRUST

"We have today limited trust with the transparency and governance process of the FIA," he declared. "Sometimes I wonder, is there really anything wrong with winning through fair means?" he added.

"Maybe there are other reasons behind the FIA proposals for a monopoly tyre. We would like those behind these ideas in the FIA to be transparent about their intentions, and this is not the case."

Michelin have won 14 of the season's 15 races but clashed with the FIA over the U.S. Grand Prix fiasco in June when their seven teams failed to start due to tyre safety concerns at Indianapolis.

The French company has promised it will refund U.S. race day ticket holders.

Michelin, who said there was no deadline for a response from the FIA, also called into question a tender to be sole supplier for the FIA's world touring car championship which went to rival brand Yokohama.

He said that remained a mystery to Michelin.

"This was done a few days after the Indianapolis Formula One Grand Prix," he said. "What was the criteria that brought about the FIA's final decision? Were the technical features of the tyres taken into account?"

He said if a tender to be Formula One's sole supplier was conducted on the same lines, Michelin would not take part unless it was a question of keeping the sport running.

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