Online music download service Virgin Digital and U.K. mobile phone retailing giant The Carphone Warehouse have partnered to provide a new digital music service to mobile customers.

Virgin Digital has become the "exclusive music download partner" for the mobile handset merchant, through an agreement in which it will power the retailer's U.K. music Web site,

The service, which is based on the interface for Virgin's existing download site, is compatible with MP3 players and mobile phones that support Windows Media Audio.

Richard Branson's Virgin Group launched the original Virgin Digital music service in late 2005; it has since been updated to offer downloads compatible with Windows Media Player.

"Rather than risk getting involved with an area in which they haven't worked before, Carphone Warehouse got on board with Virgin who has a proven track record," explains a spokesperson for Virgin Digital.

The new service also gives The Carphone Warehouse an opportunity to promote sales of phones with digital music capabilities, and could be a platform for testing the waters for the release of the iPhone, due in the U.K. Aug 20.