Singer James Blunt is suing music producer Lukas Burton, who claims he co-wrote six songs on the crooner's debut album Back To Bedlam.
Burton - who has produced tracks for Sir Paul MCCartney and Dido - alleges he co-wrote Goodbye My Lover, No Bravery, Cry, I Don't Believe, I Really Want You and Don't Lose Yourself with Blunt and is now seeking royalties from the tracks.
But Blunt insists he wrote the songs while still serving in the British army and is asking London's High Court to rule that he and EMI Publishing own the copyright to the disputed tracks.
All royalties from the disc have been suspended until the legal action is resolved.
Back To Bedlam was the best-selling album of 2005 and went double platinum in the United States.