Never-before-heard tapes of Jacqueline Kennedy speaking about the assassination of her husband, President John F. Kennedy, will be aired by ABC in a prime-time special in September, reports the New York Post.

The tapes were recorded in 1964 and became known publicly last January when History Channel, which is partly owned by ABC, said it was dropping the controversial miniseries about the Kennedy clan.

Caroline Kennedy had reportedly threatened not to cooperate on the ABC special about the tapes if the miniseries aired, the piece notes. ABC noted Wednesday that Caroline Kennedy will participate in the September special.