Cher has sued Universal Music group over $US 5 million in royalties she believes the company hid through creative accounting that she and the heirs of her late ex-husband, Sonny Bono, are owed.

Cher alleges that an audit of UMG's financial reports between 2000 and 2003 show that UMG executives engaged in creative accounting to hide royalty revenue from two Sonny & Cher compilation albums.

Reuters reperts that Sonny & Cher struck a deal in 1972 to receive up to 50 per cent of net royalties received by UMG.

Cher alleges that UMG later distributed a 1999 compilation and then attributed the income to UMG's international arm to conceal the true amount of royalties owed to Cher and Bono's descendents.