Benzema was placed under formal judicial investigation last week in connection with an alleged attempt to blackmail fellow French football international Mathieu Valbuena using a sex video.
"Which extracts were chosen? The worst," Sylvain Cormier told Europe 1.
"We're done playing now and we are announcing that we will file a complaint for violation of judicial confidentiality."
Cormier has previously said that Benzema was "totally innocent" and "played no part in any blackmail or attempted blackmail".
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Benzema has been ordered to not make contact with others linked to the affair.
(Reporting by Chine Labbe, writing by Julien Pretot; Editing by Justin Palmer)
