Three of the world's biggest music companies have decided to collaborate on a new online music service that will take on the mighty song-swapping service Napster.

AOL Time Warner, Bertelsmann and EMI have joined forces with internet video and audio giant RealNetworks to create MusicNet.

MusicNet will licence its service to companies seeking to sell music subscription services under their own brands, and could also end up doing a deal with Napster.

Notable is the absence of Vivendi Universal and Sony Music, the other two major music companies, who last month got together to develop their own rival online music service, called Duet.

EMI, Bertelsmann and AOL Time Warner will each own a minority stake in MusicNet and licence their music to the new service.

RealNetworks, which also has a minority stake, will develop the internet media delivery technology.

MusicNet will be a subscription-based service offering secure access to a catalogue of mainstream recordings, available either in streamed or downloadable format.

While the industry applauded this new collaboration, opinion was guarded because of the lack of coherent business and revenue models.

RealNetworks chief executive Rob Glaser and acting CEO of MusicNet, said: "The launch of MusicNet will catalyse an exciting new era in digital music distribution.

"MusicNet will offer consumers an easy, simple way to get the highest-quality music while also protecting the intellectual property of record companies and artists.

"We hope all the major and independent labels will join MusicNet.