Jul.21 (GMM) It is not inconceivable that world champion Kimi Raikkonen will retire at the end of this season, according to former grand prix veteran Martin Brundle.

The Briton, who is now a commentator for British television, wrote in his latest newspaper column that he senses an "unhappy and frustrated" streak in the 28-year-old Ferrari driver's demeanour at present.

Before the recent British grand prix, Raikkonen shoved a respected photographer on the grid, and at Hockenheim he struggled all weekend and dropped seven points behind Lewis Hamilton's championship lead.

"I would still be more than surprised if he retired this year, but if he wants to sign off as world champion, he needs more speed and balance in his car," Brundle wrote in the Sunday Times.

Brundle said he cannot imagine Raikkonen as a young retiree.

"I cannot easily imagine him as a businessman, a media person or a home-loving family man. I find it hard to think of him as anything other than a one-dimensional, totally focused born racer," the veteran of more than 150 races, most recently in 1996, added.

"So he would go snowmobile racing for fun, and occasional form suggests he might drink too much. You would actually worry more for him if he retired than if he was still racing," Brundle said.