Sony Ericsson has announced it will take on Nokia in the music stakes with the launch of a new service called PlayNow plus.

The new offering, which promises to give mobile phone users music on the go, will initially launch in Sony Ericsson's home country of Sweden before being rolled out across Europe.

Users will, say Sony Ericsson be able to "discover, download, play and recommend unlimited amounts of music wherever they are and whenever they like, directly over the mobile data network".

Guaranteeing "all-you-can-eat" unlimited access to millions of music tracks the company hopes it will persuade customers opting for Nokia's rival Comes with Music service.

However so far Sony is being sketchy about what happens at the end of the contract saying that users will be able to "keep your most-played music tracks" rather than all tracks.

The service is due to launch commercially with operator Telenor in Sweden in the fourth quarter of this year, with further roll-outs around the world beginning in 2009.

A special edition of the Sony Ericsson W902 Walkman phone including the PlayNow plus service will be the first phone to be launched. Sony Ericsson will include, as part of the service, 1000 of the most recent popular digital songs, with each Sony Ericsson W902 Walkman with PlayNow plus for Telenor in Sweden.

Sony Ericsson says it plans to offer other pre-loaded phones when it launches elsewhere.

As well as being able to browse millions of tracks on your phone, Sony Ericsson says it will offer a PC player allowing you to download and play as much music as you like on your PC.