The Finn, world champion with Ferrari in 2007, quit grand prix racing at the end of last season to compete in the world rally championship with Citroen.
"You never know but I will probably never return to Formula One," the 30-year-old told French sports daily L'Equipe.
"It's something I did for many years, I had many great moments. I won a world championship title, which is what I always wanted, but times have changed. Now I'm in rallying and there are many other things apart from Formula One in life."
Raikkonen would like to compete in the Le Mans 24-hour race.
"I would like to try but you need to find the right team," he said. "If you want to win, there are only two, Peugeot and Audi. One day, I hope, there will be an opportunity."
Corus chief Varin to head Peugeot
Audi aims 25% market share by 2010 end
Loeb will not compete in Formula One finale
How Audi plans to escape traffic signals
Audi, BMW, Skoda launch new models