MOTOR SPORT / Formula One: Formula One champions Renault say tyre partner Michelin's decision to quit the sport at the end of next year will not affect their performance in 2006.

"We go into 2006 as world champions, and we are determined to defend those titles," technical director Bob Bell told the team's website. "I have no doubt Michelin intend to do exactly the same. We have already seen enhanced collaboration between the Michelin teams this winter, and a rapid rate of tyre development. We are confident this will continue until the final round of 2006."

Michelin won all but one of the 19 races this year, the exception being the six-car US Grand Prix at Indianapolis that the French manufacturers' teams did not start due to tyre safety concerns.

Renault won eight races, with Spaniard Fernando Alonso becoming the youngest world champion at the age of 24. Alonso was testing in Jerez in southern Spain yesterday, his first outing since the end of the season in October, to get a feel for the reduced power he will have next year as a result of the switch from V10 engines to V8.

"I didn't feel like coming back at all because I was on vacation and my hope was to test in January," he said. "It's a big change but it's still the same to drive on the limit . . . I felt very comfortable and the times were good," added the Spaniard, who was third fastest.

Renault are not due to run their 2006 car until January 10th but Bell said it would be fired up for the first time next week. Tests with a restricted V10 had gone very well. "The drivers have noticed we need quite a different set-up on the car, so we have worked hard to understand what is required, and give ourselves a solid baseline for our work with the new car in January," he added. "Equally, we have done a lot of tyre development to begin adapting to the new regulations in this area."

Tyre changes will be allowed again next year after a season where tyres had to last for qualifying and the race.