The Moroccan playmaker has been the subject of interest from French giants Paris Saint-Germain earlier this summer but Warnock hopes he can ward off any advances and hold onto him for the upcoming Premier League season.
"It would be disappointing to see him go, but far easier for a manager to deal with," he said.
"This is the only club for him in England. It's whether anyone comes in for him from abroad that's prepared to buy him.
"It's unlikely that clubs will want him because he's not proved himself in the Premier League. He's a top Championship player with a lot of ability.
"He takes the limelight away from some of the other players who have great ability as well and that gives them a chance to shine.
"Most teams double or treble up on him. Yes, he's an enigma at times, but all top players are like that when they do what he does.
"Since he was a kid he plays how he plays. I don't think he'll change, but he is learning what we expect of him in certain situations.
"He was close to leaving, he had talks with PSG. I thought he was gone at one point."