Bertelsmann, the privately owned German media group, yesterday tightened its grip on Napster by installing one of its executives to run the controversial internet song-swapping service.

Konrad Hilbers, previously vice-president of the music business, BMG, will replace Hank Barry as Napster's chief executive.

The appointment strengthens ties between the two companies. Bertelsmann was the first of the five industry dominating music groups to break ranks from alawsuit over copyright infringement and attempt to broker a peace with Napster.

In October last year Bertelsmann took a stake in Napster and agreed to work alongside its 20-year-old founder and college dropout, Shawn Fanning, to develop a fee-paying membership service.

Mr Hilbers' first task will be to oversee the launch of the subscription service later this summer. Napster, mired in legal action, has been offline since the start of the month and there are fears that users will have switched to other song-swapping sites in its absence.

Napster enables fans to swap songs by trading MP3 files, a compression technology which turns music on compact disc into computer files. It had over 40m users before an American judge forced it to close until it could remove all copyrighted material.

Long negotiations have led to licencing agreements with MusicNet, a joint venture between BMG, EMI and Warner Music and organisations representing 150 independent labels.

Mr Barry was interim chief executive and always made clear his intention to step back. He will remain on the Napster board.

"Napster brought together through file sharing the largest group of music fans ever assembled," Mr Hilbers said. "The next step is to complete the task of transforming this phenomenon into a business that respects copyrights and rewards creators."