MySpace, News Corp.'s social networking Web site unveiled that it will start a joint venture with record companies to sell music and concert tickets online.

MySpace Music will work with Vivendi SA's Universal Music Group, Sony BMG Music Entertainment and Warner Music Group.

MySpace Music will offer free music audio and video streaming supported by advertising, paid-for MP3 downloads, ringtones, artist ticket sales and merchandise.

The business for selling downloads will allow MySpace to increase its revenue and boost its competitive advantage with the leading digital music retailer, iTunes.

According to ComScore, MySpace had a user growth of about 15 percent to 109.3 million in January, surpassing Facebook's 100.7 million.

News Corp. shares declined by 8 cents, to $19.51 in New York Stock Exchange and have dropped by 4.4 percent this year.

MySpace and Facebook compete for advertisers who target Web users based on their age, location and hobbies.

Other companies involved in selling music include Amazon.com Inc., which sells downloads, and CBS Corp.'s Last.fm, which offers a streaming service.

According to a research by EMarketer Inc., Ad spending on social networks in the U.S. was forecasted to increase to $2.7 billion by 2011.