Lotus boss Eric Boullier believes that Kimi Raikkonen's final decision on whether to stay with his current team or move to Red Bull will not just be based on the speed of the car.
With Raikkonen emerging as one of the leading contenders to replace Mark Webber at Red Bull in 2014, Boullier accepts that there is no guarantee he will keep hold of his star driver for next year. Although Red Bull currently has the better track record and faster car, Boullier thinks the quality of the machinery is not the only factor that matters to his Finnish driver.
"Red Bull is chasing Kimi and we want to keep Kimi," explained Boullier. "Kimi will decide what he wants to do, and he will decide what is best for him.
"He knows what he has with us; he can guess what he has with Red Bull. Now we are talking with him and he is seeking some understanding of where we are going, in terms of building with the new ownership. He is happy with what he has, so we will see."
He added: "The environment must suit him. We will keep improving the team performance and we will keep going this way to match Red Bull's team performance as much as possible. Being part of the environment to build it around yourself is the nicest challenge for a driver."
Red Bull boss Christian Horner believes, however, that Raikkonen's decision will come down simply to which team offers him the best chance of victory.
"At the end of the day it will be equipment at their disposal," he explained. "Any drivers will want the most competitive environment at their disposal, but we are not just looking at Kimi Raikkonen.
"We have [Toro Rosso drivers] Daniel Ricciardo and Jean-Eric Vergne, who are true contenders for the seat. We need to take a bit of time to look at all the options that are available."