Birmingham knocked back in trying to sign Man City keeper Hart
Hart moved to St Andrews on a season-long loan from Manchester City in the summer and has impressed hugely for the Blues.
McLeish told The Guardian: "City will take Joe Hart back at the end of the season.
"There is no chance of us signing him in January. We asked the question and they said that won't happen. We never had an option from City to buy him.
"He has the comfort of knowing City really want him and he is part of their future."
The Scot believes Hart could still be with Birmingham next season if Roberto Mancini agrees to another loan deal.
"It is City's policy and they said that [Hart going back]," added McLeish.
"When Mark Hughes went in they revamped the youth side of it and they brought in Mike Rigg who is chief scout. They were going to be putting in an active policy of having young players in place as well as bringing in the big names.
"Joe Hart remains a big part of the future. But you couldn't rule out that Joe stays with us in the summer.
"They said he was going out for experience to improve and he has improved. It doesn't preclude him from coming back and we can negotiate with City for another year."