The 25-year-old Courtois has been ever-present in Chelsea's starting line-up since permanently signing for the London club in 2014, helping them win two league titles and one League Cup, and has featured in every match for Conte's team this season.
Courtois' contract expires in 2019 with the shotstopper saying he would hold extension talks after the end of the campaign.
"I can say Courtois is one of the best, maybe the best goalkeeper in the world," Conte told reporters. "And he is a very important player for Chelsea. But the renewal of contract is a task for the club.
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"He knows very well my opinion and my thoughts about him... As you know very well, if a big player decides to not sign a new contract it is very difficult for the club to face this issue.
"These types of situations are not simple but every club has to try and solve all these situations."
Chelsea are third in the league and travel to fifth-placed Liverpool on Saturday.
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