The midfielder is on-loan at Leicester from AS Monaco.
"With Tielemans, I think the issue that Leicester will have is that there are midfields in the top six that need strengthening," said Neville.
"He is 21-years-old, available they say for £40m. He's proved himself in the Premier League, almost like a dress rehearsal at Leicester.
"Leicester could struggle to keep him because of the fact that other clubs may want him."
He added: "I can understand the supporters will like to watch a young player like that and I'm sure the club will do everything they possibly can to bring him in."