Britney pulls out of Jackson concert

Spears had been rehearsing her duet with Jackson

Britney Spears has pulled out of performing at Michael Jackson's gala concert just days before she was to join the superstar on stage.

The singer was forced to cancel her appearance, despite having rehearsed with Jackson, because of a deal she has with a television broadcaster.

The 19-year-old was supposed to duet with Jackson on The Way You Make Me Feel at Friday's concert in Madison Square Garden in New York to mark the release of his new album Invincible.

Two concerts, on Friday and Monday, also celebrate Jackson's 30th anniversary in show business and the superstar will reunite with his famous brothers for the performances.

Jackson is to celebrate 30 years as a performer

But because it is to be broadcast on the CBS network, Spears had to cancel because of her exclusive deal with rival HBO.

Her spokeswoman told the New York Post: "Britney did have to pull out - and she's very upset about it."

Among the artists and celebrities scheduled to perform and pay tribute to Michael Jackson are Whitney Houston, Gladys Knight, Ray Charles, Britney Spears and Quincy Jones.

Jackson 5

Actors billed to appear include Marlon Brando, Elizabeth Taylor, William Shatner, Willem Dafoe and Macaulay Culkin.

Jackson has been in the limelight since the age of five

The event will mark Jackson's first live performances on a mainland stage in 11 years and the first reunion with his brothers, the Jackson 5 (Jackie, Tito, Jermaine, Michael and Marlon) and the Jacksons (Jackie, Marlon, Tito, Michael and Randy) in 20 years.

Ticket prices for Michael Jackson: 30th Anniversary Celebration range from $45 (£32) to $2,500 (£1,760).

The first single from Invincible, Rock My World, was due to be released in September but there are reports that the release date may have been put back.