The council serves as a court for consumer complaints.

"It is important to show that we have a broad alliance of consumer bodies backing us, and if we win this case, I hope they will follow in our footsteps and take action," he said.

The consumer ombudsman said that consumers must be able to choose which music device they wish to use to listen to music bought from iTunes.

"It's a consumer's right to transfer and play digital content bought and downloaded from the Internet to the music device he himself chooses to use," Thon said and added: "iTunes makes this impossible or at least difficult, and hence, they act in breach of Norwegian law."

iTunes has until November 3 to respond, before the case goes to the Market Council, the ombudsman said.