Hazard is being linked with a move to Madrid this summer.
And Cesc told Cadena SER: "I do not know what he's going to do.
"I only know that he is a fan of Real Madrid.
"I also know that he is very happy with Chelsea, just like his family. He is the leader of the team. He has to make a decision. If he does not extend before the start of the summer, he will have to make a decision.
"He is 28 years old and it is in any case the perfect time to leave. In any case, it is a very personal decision."