Spurs have fielded a bid from Werder Bremen for the Croatia international.
"There is a German club (Werder Bremen) that have come in for him. They have offered good money for him but I'm not keen to lose Niko," Redknapp said.
"He is a good player, a fantastic player. I don't think he wants to go to Germany and play.
"I don't think he feels that's an option for him. If that's the case then he will stay here and that's great for us as well."