Mourinho was speaking at a conference in the Turkish capital Ankara and highlighted the difference in fan culture between Spain and England as one of the main reasons why he may return.
He told AS: "I have signed until 2016, but in a club like Madrid if you lose two consecutive games they can cancel your contract.
"I hope to do as well as possible in these years as I am better than ever with 10 years of experience. In 2016 my daughter will be starting university and I would like to choose in which city she studies.
"London was distinct for me. I had a normal life there. In England the people are not interested in your personal life, but that is different in Spain and Italy. I need to protect my family."