LONDON (AFP) - Britain's Jenson Button will stay with the BAR-Honda team for the 2005 season, it was reported.
The driver had wanted to return to drive for Williams, where he started his F1 career in 2000, but that hope was dashed by a ruling from the Formula One Contract Recognition Board (CRB) in Milan, said the BBC.
Legal presentations from both teams were heard in Milan on Wednesday before the verdict was delivered.
The 24-year-old Button is third in the drivers championship, behind world champion Michael Schumacher and Rubens Barrichello, going into the final race of the season in Brazil on Sunday.
BAR insisted they had a binding deal with Button while the driver's management team claimed they had discovered a loophole in that contract.
In August, Williams said they had signed a deal with Button for 2005 and beyond but Wednesday's decision leaves the team searching for a teammate for Mark Webber next season.
Both Williams' current drivers, Juan Pablo Montoya and Ralf Schumacher are leaving after the end of this season - Montoya is going to McLaren and Schumacher to Toyota.