A former member of ABBA can cash in 85 million kronor (US$12 million) after winning a court case against the national tax authority.

Bjorn Ulvaeus' legal adviser says a court approved his appeal against a decision to increase the amount of his income it considered taxable.

Ulvaeus signed contracts to hand over the rights to his song royalties to different companies. He claimed that excluded them from his personal income.

Swedish authorities had claimed the deals were shams and that the star still had access to the money and should include them as his income.

Ulvaeus was part of the Swedish pop group in the 1970s and 1980s, and has since co-written several musicals including the hit 'Mamma Mia!', which was made into a recent film.