Real Madrid are pushing hard to sign the Croatia midfielder, but Levy refuses to budge from his €40 million asking price.
Stimac told AS: "Yes (it's a complicated situation), because on the other side is a guy who does not fulfill the promises he makes. Daniel Levy promised a year ago that if he got an offer from Madrid he'd let him go. And when the offer came, he changed his mind.
"I think this guy tries to become famous in the world of football, but that's not the way to go. When you promise something you always have to comply. He did the same with (Dimitar) Berbatov before he joined Manchester United. That was on August 31."