Online music service OD2 has said it is adding nearly one million new tracks to become the biggest internet music service in the world.
OD2 provides the songs for services such as Tiscali and HMV
The service, which was bought by US service Loudeye earlier this year, will boost its catalogue from 350,000 tracks to more than 1.3 million.
This would make it larger than Apple's iTunes or Napster, both of which have more than 700,000 songs.
The OD2 catalogue increase is expected to take place later this year.
OD2, which was co-founded by rock star Peter Gabriel, is a Europe-only service which licenses its technology to other sites including Mycokemusic, HMV, Virgin and MTV.
Charles Grimsdale, Loudeye's international business president, said the new deal to use Loudeye's catalogue will be of benefit to both parties.
"OD2 and Loudeye share virtually identical goals, vision and passion for the future of digital music .
"This deal will allow OD2 to reach customers in the US while allowing Loudeye to enter the European market," he said.
OD2 announced on Thursday that its sales had gone up markedly in the second quarter of this year.
Europe is seeing big growth in online music services
It said its sales increased by 28% week-on-week following the iTunes launch in the UK, France and Germany, and by 22% the week that Napster launched its European operations.
"These results show the European market is entering a phase of explosive growth," Mr Grimsdale said.
OD2 have attributed part of their growth to the launch of their SonicSelector jukebox plug-in, which allows the service to be used through the common Windows Media Player application.
It allows people to listen to the service's catalogue for just 1p a track through a streaming service.