The pressure grows on Jenson Button

With Italy's Jarno Trulli, who has joined from Jordan, virtually guaranteed the other seat that could leave Britain's Jenson Button searching for a drive if Williams - as seem likely - do not take up their option on him.

"We have followed Fernando's performance very closely this season," said Briatore.

"He did an excellent job and we therefore decided that it was important to integrate him quickly into the Renault F1 programme.

"As our test driver next year, Fernando will have the opportunity to fully develop his talent and, in the seasons to come, I'm sure that he will be a strong asset in the team's challenge for the championship."

Button, 21, had a good debut season with Williams in 2000 scoring 12 points but was loaned out because of the Grove-based team's contractual commitments to Colombia's Juan Pablo Montoya.

The Frome-born racer found life far more difficult last season and managed just two points in the Benetton. It was reported that Briatore had given him the chance to walk away from his two-year deal.

Alonso's move to Renault leaves the struggling Minardi team looking for a driver for next season to partner Malaysia's Alex Yoong.