There is a risk Jenson Button will not line up on the formula one grid in 2009, fellow British driver David Coulthard admits.

Coulthard, who contested his last of 247 grands prix last month, is a close friend of 28-year-old Button, whose contracted employer Honda shocked the motor racing world by announcing its withdrawal.

Button is now hoping a buyer can be found before the start of the 2009 season next March, or must switch to another team.

"There's a lockdown at the big teams at the moment, so they're not going to kick anyone out to make way for Jenson right now," Coulthard, who contested the Race of Champions along with Button at Wembley stadium, said on Sunday.

Coulthard admitted: "He may have to wait on the subs' bench until the following year."