Promoters said the US group and the "Dreamgirls" Oscar winner would perform at the "Michael Forever" tribute in Wales on Oct. 8, along with Christina Aguilera, Cee Lo Green and Motown legends Gladys Knight and Smokey Robinson. The tribute has the backing of Jackson's mother Katherine but siblings Randy, Germaine and Janet have said they will not be attending.

Black Eyed Peas co-founder will.i.am said Jackson's music had been an inspiration to him growing up in Los Angeles, and recalled working with the "Thriller" singer in 2007. "The Black Eyed Peas wouldn't miss being at the Millennium stadium for this gig on Oct.8: We all owe Michael such a lot," will.i.am said. Grammy-winner Hudson, a former "American Idol" contestant, won an Oscar for her role in the 2006 movie musical "Dreamgirls."

The tribute concert comes more than two years after Jackson, 50, died in Los Angeles. But the venture has been plagued by problems, including criticism by some Jackson fans and the official administrators of Michael Jackson's estate over the line-up, ticket prices and confusion over charity donations.