Lady Gaga has posed pretending to be lying dead in a coffin to mark World Aids Day today (December 1).

The singer is one of a number of musicians and celebrities involved in a campaign organised by Alicia Keys called Digital Life Sacrifice.

Part of Alicia Keys' charity, Keep a Child Alive, the campaign aims to keep the celebrities off social networks from Tuesday (November 30) until the charity raises $1 million.

A picture of Lady Gaga in a coffin has been posted on the star's Twitter page along with the number fans need to call to “awaken Mother Monster”.

Keys said of the campaign: "It's really important and super-cool to use mediums that we naturally are on," Keys told the Associated Press.

Other supporters include Justin Timberlake, Jennifer Hudson, Ryan Seacrest, Elijah Wood, Serena Williams, Kim and Khloe Kardashian, Janelle Monae and Keys' husband, Swizz Beatz.

(by Jason Gregory)