Robert Kraft is ankling his post as prexy of Fox Music after 18 years with the studio.Fox Music prexy Robert Kraft, who has overseen music for 20th Century Fox juggernauts including “Avatar,” “Titanic” and “Ice Age, has decided to leave his post. Kraft has been the chief executive of Fox Music since 1994 and became president in 1998. He supervised the music for all of the Studio’s films, including “Waiting to Exhale” and “Moulin Rouge!” and “Rio.” He also supervised the music for Fox Television series including “Ally McBeal,” “The X-Files,” “24,” “American Dad,” “Family Guy,” and “The Simpsons.” Since Kraft became Fox Music’s chief executive, the division has amassed worldwide sales of over 65 million albums, producing three platinum, six multi-platinum and six gold records, according to a studio release announcing Kraft’s departure. Kraft is creating a new venture to develop musical films and television shows, according to the release issued Friday. “I’ve spent the past 18 years at Fox Music being involved in the creation of wonderful film music, and in the process have had the distinct pleasure of working with some of the most creative composers, filmmakers, and recording artists in the world,” Kraft commented in the statement. “I’m very proud of what Fox Music has accomplished during my tenure, and I know the division will continue to inspire both music and film audiences for a long time to come.” Kraft’s decision to depart came before the announcement that 20th Century Fox chairman Tom Rothman would ankle his post at the end of the year, according to insiders at the studio.