Singer Michael Jackson has three children

The court in California backed a ruling that Ms Rowe's 2001 agreement to end her parental rights was invalid because the judge had made a procedural error.

Ms Rowe has been seeking custody of Michael Jnr and Paris since the star's arrest over child abuse claims in 2003.

Mr Jackson was acquitted of all 10 charges against him in June last year.

Radical group

Ms Rowe, 46, the mother of Mr Jackson's two older children, was married to the singer from 1997 to 1999.

She agreed not to contact the children following their divorce in 2000, and gave up her parental rights in 2001.

But in 2004 Ms Rowe persuaded a Los Angeles Superior Court judge to overturn the child custody agreement.

Rowe and Jackson divorced in 1999 citing irreconciable differences

She cited the child molestation accusations of against Mr Jackson, and his reported links with the radical group the Nation of Islam, as legal grounds.

When Mr Jackson was acquitted of child abuse charges last year, the lower court refused his request to overturn the 2004 order.

He then appealed to California's 2nd District Court of Appeals, but the court ruled against the singer on Wednesday.

Mr Jackson's lawyers declined to comment on the ruling.

The singer has a third child, Prince Michael II, by an unknown mother.