Robbie Williams is to release this year's official fund-raising song for U.K. charity Sport Relief.

"Morning Sun" -- taken from the U.K. pop singer's 2009 studio set "Reality Killed the Video Star" (Virgin/EMI ) -- will be released in the United Kingdom March 8, with all record company profits and artist royalties from digital single sales of the track in the U.K. set to go to the charity.

Royalties from the song's writers and their publishers -- Williams and Farrell Music; Danny Spencer, Kelvin Andrews and Chrysalis Music; Richard Scott, Scott Ralph and EMI Music Publishing; Don Black and Sony/ATV Music Publishing -- will also be donated to Sport Relief.

Commenting on being chosen to represent the charity, Williams said in a statement: "I am very happy to donate my time to help Sport Relief and I thank my co-writers for doing the same."

Launched in 2002 by the Comic Relief charity, Sport Relief is one of the U.K.'s biggest regular fund-raising events. It takes place every two years, with the 2010 activities scheduled for March 19-March 21. The charity raises money for humanitarian projects in the United Kingdom and overseas.

As previously reported, Williams is due to receive the outstanding contribution to music award at this year's BRIT awards, which takes place Feb. 16 at London's Earls Court Arena.