Diana Ross (L) does sound check at the opening nite of the US Open at the 'Billie Jean King Tennis Center' in Queens. New York City, USA - 28.08.06 and Beyonce Knowles (R) performing live at Glamorama at Chicago Theatre. Chicago, Illinois - 29.09.06

The soul diva made it clear she wasn't a fan of the project when it first appeared as a Broadway musical, and now sources claim she's planning a subtle 'diss' campaign to ruin the film's Academy Award chances.

Los Angeles Times' Hollywood insider TOM O'NEIL claims "the original Dreamgirl" could create the kind of negative publicity that turns Oscar voters off if she "publicly disapproves" of the film, in which Knowles plays her.

He says, "A longtime friend and colleague (of Ross) tells me that Miss Ross hates Dreamgirls because she feels like she's been ripped off, like its creators changed just enough key elements of her story so they didn't have to pay her royalties and then refused to give her any input on how her story would be told."

The singer's biographer J RANDY TARABORRELLI is, however, convinced Ross will not blast the film.

He says, "I think that Diana has decided that there's not much she can do about this and she wisely knows that there wasn't much (R+B legend) BILLIE HOLLIDAY's estate could do about her when she did (1972 biopic) LADY SINGS THE BLUES."

Source: WENN