Referring to 37-year-old Raikkonen, Alesi told La Gazzetta dello Sport: "He is very much a loved Ferrari driver.
"We are talking about a guy who really loves driving and is a real point of reference for the whole environment at Ferrari.
"The decision to keep Kimi consolidates this atmosphere, as neither Vettel nor Kimi is jealous of the other.
Indeed, Alesi thinks that the next step for Ferrari will be to announce a new contract for its de-facto 'number one' driver, German Vettel.
"I think Vettel will renew as well," he said. "A house is built upon its foundation, but I also think it's true that if there is a driver other than Seb at Ferrari in 2018, he will also have no problems with Kimi."
Ferrari sit 39 points behind leaders Mercedes in the team rankings ahead of this weekend's Belgian Grand Prix.