The teenage winger has a first Premier League goal and is becoming a regular starter for Martin this season.
Dibling, who rejected Chelsea two years ago, is on the radar of Manchester United chief Dan Ashworth this season.
Martin told the Daily Echo: "I think when you're 18 and you're playing in the Premier League at the level he has, then every club in the world probably looks at you.
"He's ours. The club have turned down bids for him previously since I've been here. It's not a secret to people who have watched under-21s football.
"He left the club and didn't enjoy it where he went so he came back. We ultimately want what's best for him and he has a great support network around him.
"We have to make sure he is constantly enjoying it and that we are playing a style that he can flourish in.
"The speculation is nothing for him or for me. We are in a strong position and I'm sure we will look at securing and strengthening that even more.
"If he carries on doing what he is doing then he will deserve that. He just needs to focus on football and concentrate on what he is doing."