However, Mowbray insists that the youngster would benefit more from continuing his development at the Ricoh Arena.
"These big teams might think that they'll able to get a player from a League One club but I have to say I think the owner is pretty resolved on the matter," he told the club's official website.
"James has only played something like 14 games at League One level. My advice to James has always been to let his career develop and to play football.
"Here, he'll be able to let his talent flourish where he is appreciated but if he moved to a big club, he isn't going to get in their first team. He should in a place where he'll enjoy his football and let the talent grow."
Maddison made his professional debut for the Sky Blues in August 2014.