The highly-rated 22-year-old keeper is currently on a season long loan deal with Birmingham City, who would like to take Hart on loan for another year.
However, when asked the question regarding the England international's future, Mancini said: "Joe Hart is a good goalkeeper, who next year could be an important goalkeeper for England and Manchester City.
"He is only young and probably he will stay with us.
"But it is not an important issue just now.
"We must concentrate on our games and stick with what is happening this season."