He has been unsettled since returning to Spain and has recently been linked with a possible move to Liverpool.
"We will see at the right time, but yes, there is always a possibility," he said when asked about a move back to France.
"I have, however, decided to come back to Madrid for one season and it would need to be exceptional circumstances not to follow my idea.
"I could leave if I don't play and don't take part in the good and bad moments of the team."