Larsson is out of contract at the end of the season and McLeish is keen for the midfielder to sign a new deal with the club.
Blues’ manager said: “Yes, we want to keep Seb. He’s certainly been one of the stars performance-wise this season.
“I think he’s taken his game to a new level. Whether that’s because his contract is nearly out I don’t know.
“Sometimes you see that with players in the last year of their contract.
“Seb is an international now and is a regular in the Sweden team, whereas maybe he was a bit-part player over the last couple of seasons.
“Maybe that was because he wasn’t on top form the last couple of season, but he certainly is now.
“He is one of the first picks in our team and it’s up to every player to maintain that kind of level.”
McLeish added: “Seb can only talk to European clubs. He can’t talk to anybody in the UK but we’re not daft and we know how football works.
“He’s certainly free to talk to foreign clubs in January.
“It’s a concern because, if we’ve not done anything about it, then Seb has decisions to make.”
