The 34-year-old, who comes to the end of his contract in the summer, has been linked with a switch away from Stamford Bridge. Di Matteo has made it clear that the Champions League winners want to keep the England international but has suggested that Lampard has yet to make a decision.
"Ultimately that's between the player and the club to agree a new arrangement," Sky Sports News quotes Di Matteo as saying.
"I'm not aware how the discussions are going at the moment. If there's a willingness from both sides, he will remain with us. He's been a fantastic player for us over a decade, so it would be nice for him to finish his career here."