The 50-year-old has endured a difficult season in the Spanish capital, with his side trailing Barcelona by 16 points in La Liga and reports of fallings-out with some of the club’s senior players.
Mourinho has been linked with a return to his former employers Chelsea in the summer, with Rafael Benítez only the interim coach at Stamford Bridge.
But Calderón expects the ex-Inter Milan manager to move to PSG.
“It seems he will leave. It seems very probable the will go to Paris Saint-Germain,” Calderón told talkSPORT.
“He say that he’s going to stay but I don’t think so. Things have gone too far and Madrid are unwilling to accept any more of this behaviour.”
Calderon, who was president between July 2006 and January 2009, signed Ronaldo in a world-record £80m deal from Manchester United.
And the 61-year-old revealed Ronaldo’s agent Jorge Mendes, who is also Mourinho’s representative, wanted Calderon to appoint the former Blues boss as Madrid manager.
But the former Los Blancos supremo says he turned down the chance to employ Mourinho because he claims that the coach’s behaviour is not befitting a club of Madrid’s stature.
“Of course. I always said that it’s the president’s [Florentino Pérez} fault. Mourinho’s been behaving like that all his life. So the one who is signing him is assuming he’ll be the same,” he added.
“I could have. At the time when I signed Cristiano Ronaldo, his and Mourinho’s agent, Mendes, was talking to me about the idea of signing Mourinho.
“I said his behaviour was not according to the history of Real Madrid.”
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