Mourinho has spoken of returning to England in the past week.
But Karanka says: "The head of the coach is only here, he does not think of anything other than Real Madrid and the next game. I do not talk to him about his future, I'm not interested.
"The feeling that he gives me is to work on the next game. Neither ask nor do I care what he will do.
"In his head there is nothing but Real Madrid and the next game."