AceShowbiz -

Rumor has it, Madonna and Mariah Carey will make contribution to Michael Jackson tribute album. According to Daily Star, Madonna is said to cover either Michael's single "Beat It" or "Billie Jean" in addition to "Rock With You", "She's Out of My Life" and "Bad", while Mariah reportedly will sing "Who's Loving You" and "Ben".

Also being suggested to be involved in the set is Robbie Williams. The former member of boyband Take That is believed being recruited to sing his rendition of "Man in the Mirror". He previously said about being saddened by Michael's death. "It's all so very sad," he shared. "I couldn't get a lyric to fit on one of the new songs, so when Michael passed away I rewrote it with him in mind."

Other big singers claimed to be featured in the project are Beyonce Knowles, Whitney Houston, Usher, Stevie Wonder, Diana Ross and Lionel Richie. On the idea of having star-studded compilation for Michael tribute album, a source explained, "The idea came from the memorial concert. Many fans asked if cover versions would be released and it seemed a wonderful idea."

"Some the biggest stars in the world have indicated they'd like to take part to pay their own respects and tribute to the King of Pop. This covers album is sure to be a massive worldwide hit with fans and could raise a fortune for Michael's favorite charities."