The Belgian, 25, has only one year left on his current deal but is yet to sign a new contract at Stamford Bridge.
“I’m committed to Chelsea. I have a contract until next year and I will be here. I will do my best for it,” Courtois told the Evening Standard.
“Obviously there is no extension signed but I don’t think now is the moment to do it. I think it is better to wait until the end of the season. All I can say is I’m committed to Chelsea and also committed for next year.”
Courtois, who posted a poor performance as Chelsea lost to 3-0 Barcelona in their Champions League round of 16 tie in midweek, has been linked with a move to Real Madrid and he admits he is not happy with the speculation.
“It’s easy when you have only one year remaining that other people might say something,” he added.
“I’m a bit annoyed by it because it’s a talking point and it’s a thing people want to dwell on.
“But I think the focus now should be on winning our League games to get a top four finish and back in the Champions League for next season as well as going through in the FA Cup.”
Chelsea face Leicester City on Sunday in the FA Cup quarter-finals.