Coulthard would welcome Alonso at Red Bull

"I've been asked several times who I think should take over my seat next year," Coulthard wrote on his column for the ITV website.

"That's a decision for the Red Bull management, but the common sense answer is that it should go to the quickest guy with a proven track record who is available.

"That might be Fernando Alonso for instance; if the team could get him that would make sense because he has great credentials as a double world champion.

"But if we assume he's not available, then it's completely logical to take Sebastian Vettel, who is within the Red Bull family, is performing well at Toro Rosso and naturally wants to progress to the larger team. I'm confident he would do a very good job for our team."

Coulthard announced last week that he would leave Formula One racing at the end of the current season, after 15 years in the sport.

The Scot says he was tempted to announce his decision in Canada, where he scored a podium finish and where he told his team about it.

"I informed the team of my decision over the Canadian Grand Prix weekend," he added.

"When I went on to finish third in that race, I did wonder whether I should make it public then because it might be my last time on the podium.

"But I'd already decided that Silverstone was where I wanted to announce it, partly in order to give me time to meet with Dietrich Mateschitz to discuss my future role in the team."

Coulthard also admitted returning to racing is a possibility for the future, but he made it clear he will not be competing next year.

"I haven't said I'm hanging my helmet up because obviously I intend to test for RBR, and I also don't want to rule out the possibility that I will compete in another form of racing in the future.

"But I'm not looking to enter another racing series next year, because at the moment that's not where my mind is; my focus is on concluding this season as best I can and then helping the team adapt to the 2009 formula.

"Further down the line, who knows? If there's the opportunity to race something that excites me then I'll look at it. But it's certainly not part of my thought process right now."