SILVERSTONE, England - Ferrari's Kimi Raikkonen, 2007 Formula 1 champion, expects to retire when his contract runs out at the end of 2015.The fan favourite, who won his title with the Italian glamour team in 2007, returned to Maranello this season on a two-year contract but the Finn has struggled to match team mate Fernando Alonso in the eight races so far with only 19 points to the Spaniard's 79, his best finish seventh.Raikkonen, now 34, said: "Until my contract is finished - then I will probably stop. That is what I think is going to happen."END OF DAYSRaikkonen took two years out of F1 to compete - without much success - in the World Rally championship before coming back in 2012 to Lotus."When I feel it's time to finish F1 it's time to finish," he said. "Even doing something else at the same time makes no difference because the decision is about F1 and if it is the right time to stop."The 2014 F1 season is approaching halfway, a stage where speculation about likely driver moves starts to pick up speed. Raikkonen's results have inevitably focused attention on the famously taciturn driver while Alonso's future at Ferrari has also been questioned after apparent overtures from his former McLaren boss Ron Dennis.Jenson Button, the 2009 champion, will be out of contract with McLaren at the end of the season but has said he wants to stay. Lotus' French driver Romain Grosjean is also starting to feature in the rumour mill.Stay with Wheels24 for the 2014 British GP this weekend.