XM Satellite Radio must use advertising on music channels owned by Clear Channel Communications, XM revealed in a March 3 filing with the U.S. Securities and Exchange Commission.

Clear Channel, which gained control of four XM music channels in a 1998 investment, “is entitled to include commercials on the music programming it provides XM,” an arbitration panel ruled.

“The parties have agreed to abide by the panel’s preliminary decision, to include commercial advertising and share advertising revenue on all Clear Channel-provided talk and music programming starting in March 2006,” XM said in its filing. The satellite radio operator also agreed to pay XM $2 million for the period when commercials were not included on the channels.

The commercials will be added to KISS, MIX, Nashville and Sunny, as well as a fifth music channel under development, according to a letter to subscribers from Eric Logan, the company’s executive vice president of programming, posted on XM’s Web site.

XM plans launch four new commercial-free channels throughout the next few months to offset the four channels that now will include commercials and allow XM to continue advertising itself as providing the most commercial free music stations. The additions would give XM 69 commercial-free music channels, compared to 68 for rival Sirius Satellite Radio.