Sony will introduce a new hard disk-based MP3 player in December, and will offer software upgrades for earlier players with hard disk storage so they can play MP3s too.

The 20GB NW-HD3 can play MP3 files, but is otherwise similar to its predecessor, the NW-HD2, Sony spokesman Shinji Obana said.

The device supports Sony's proprietary ATRAC3plus compression format, as used in MiniDisc. Sony previously resisted adding MP3 support, arguing that it is inferior to the ATRAC, which also includes digital rights management support.

However, Sony hasn't been able to ignore rising demand for online file sharing and PC-based jukebox software, the growing popularity of products such as Apple's iPod and the emergence of smaller local competitors such as iRiver - all of which support and use MP3.

Sony will put the new player on sale in Japan and the UK in December and the rest of Europe in January. The company is considering sales in the US and Asian nations outside of Japan but has yet to make any decision, he said.

The Japanese launch is scheduled for December 10 - two months to the day since it launched the NW-HD2 player, and five months to the day since it launched the NW-HD1, the first Walkman-brand hard-disk drive based music player.

Sony also said it will offer owners of the NW-HD1 and NW-HD2 players the chance to add MP3 support. Owners will be able to have the firmware in their players upgraded at a cost by taking or sending it to a Sony service centre, the company said.

The new device will cost £249.