A massive iPod download war is set to break out. As Apple is believed to be readying its film download service for launch tonight, rival online song service eMusic starts across Europe.

It will be the first time a major provider has offered songs for Apple's iconic player, breaking the California company's monopoly on selling iPod songs.

Whereas users of Apple's iTunes online store pay 79p a track, subscribers to eMusic can get songs for as little as 17p each, although the service only has about

1.7 million tracks in its catalogue, compared with the three million available from Apple.

However, eMusic's database of songs from a growing independent sector includes familiar names such as Johnny Cash and newer acts such as Basement Jaxx, who are set to play at eMusic's lavish launch party tonight. eMusic, which has more than doubled its US market share this year, largely at the expense of iTunes, says Apple's monopoly is not good for customers.

"We believe that the iTunes monopoly in Europe is over," said former Apple employee David Pakman, eMusic's chief executive.

Apple has been undisputed number one in the digital download world, and is believed to hold about 80 per cent of the UK market.

But industry experts say it could lose out to a raft of new, lower price services and "free" sites such as SpiralFrog, due to start here next year.

Arch rival Microsoft is also expected to launch a new online store this year to coincide with the launch of Zune, its "killer" rival to the iPod, due in November.

Apple has been criticised for only allowing users to buy songs outright. Rivals work on a monthly fee for as much music as customers want.

Leanne Sharman, Napster's UK general manager, said subscription was the way forward. "The mobile industry began as a pay-as-you-go business reliant on handset sales," she said. "Now it's subscription that drives the business."