The Belgium international’s future at the west London club has been a source of debate in recent months.
Real Madrid have reportedly made signing a goalkeeper a top priority in the summer transfer window following a difficult 2017-18 season.
Los Blancos are in fourth place in La Liga and a staggering 19 points adrift of Barcelona despite winning the title at a canter last term.
Courtois has won two Premier League titles and the League Cup over the past three and a half seasons after his return to Stamford Bridge from a three-season loan at Atletico Madrid.
The Chelsea number one’s former partner and his two children still live in the Spanish capital to provide Courtois with a possible incentive to move back to La Liga.
The defending Premier League champions are set to open negotiations with Courtois over extending his current deal which is set to expire in 2019.
When asked about how much signing a world-class goalkeeper such as Courtois could cost Real Madrid, Stoke midfielder Adam told The Debate on Sky Sports on Wednesday night:
“I’d be wanting £150m at least [for Courtois].”
Chelsea FC are in fourth place in the Premier League table.
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