The Chelsea FC shot stopper is facing an uncertain future at the west London side given the Belgium international has 12 months remaining on his current deal.
The Blues goalkeeper has been regularly linked with a move to Real Madrid over the past few seasons as a potential replacement for Keylor Navas.
Chelsea FC sent Courtois out on loan for three seasons at Atletico Madrid where he won the La Liga title and reached the Champions League final.
Courtois’ former girlfriend and two children are still in Madrid to provide one reason why the Belgian goalkeeper would like to return to Madrid.
Sunday Times reporter Castles confirmed that Courtois is looking to leave the 2017 Premier League champions and secure a return to Madrid.
“He has told Chelsea he won’t sign a new offer,” Castles told the Transfer Window podcast.
“He is hoping to move this summer. He is prepared to wait to be out of contract to move on a free.
“He would like a move ideally to Real Madrid. He sees the possibility of Atletico Madrid if Jan Oblak leaves.
“Courtois is a serious problem for Chelsea. Chelsea value him at 100m. I don’t see them getting that money.”
Antonio Conte’s side finished in fifth spot in the Premier League table to miss out on a Champions League spot next term.
The Italian coach is expected to leave Stamford Bridge this summer amid talk of Maurizio Sarri taking over the reins at Chelsea FC.
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