Courtois has been on loan with the Madrid club since he signed for the Blues in the summer of 2011, winning the Europa League, Copa del Rey and Uefa Super Cup with the club.
|5/1||Atletico Madrid are 5/1 with Bet365 to win the Champions League|
But while there is nothing in the loan agreement to automatically prevent Courtois facing Chelsea in the last four, Atletico would have to pay the Londoners upwards of £8 million.
"If we draw Chelsea, Courtois won't play. It is a figure we cannot pay," Cerezo told Onda Cero.
Courtois is said to be unwilling to return to Stamford Bridge unless he can be assured of first-team football - a guarantee Chelsea cannot make due to the continued fine form of Petr Cech.
Cech is contracted with the Blues until the summer of 2016 and last week Goal reported that Courtois is on the verge of agreeing a deal to keep him with Atletico for another season.