London, Aug 30 (IANS) Union bosses at the Screen Actors Guild (SAG) have warned members not to take part in the documentary about late pop legend Michael Jackson's doomed "This Is It" tour.

Sony Pictures have purchased rehearsal and behind-the-scenes footage from concert promoters AEG Live, filmed at Los Angeles' Staples Center, as Jackson prepared for his residency at London's O2 Arena.

The studio planned a two-week run for the film beginning Oct 28. However, SAG bosses have announced that the film's producers have not agreed to the minimum basic terms and conditions for performers and background actors employed on the project, reports contactmusic.com.

A statement from the union reads: "Guild members are reminded of their obligation not to accept employment on any non-signatory project, as well as their obligation to confirm with the guild that a project is signatory. Employment on any non-signatory project within the guild's jurisdiction may subject a member to a Rule One violation."

The union did not have jurisdiction over rehearsals and behind-the-scenes footage during filming, which it expects to be a feature release.

Jackson was set to take the stage in July, just weeks before he died from a suspected cardiac arrest June 25.