London, Dec 7 (IANS) Popstars Lady Gaga, Justin Timberlake and Usher are set to rejoin Twitter and Facebook after successfully helping to raise $1 million for the children’s charity of Alicia Key.

The pop superstars agreed to sign off of all social networking sites as part of a new campaign, Digital Life Sacrifice, to raise donations for Key’s Keep A Child Alive Foundation, contactmusic.com reports.

The celebrities, which also included Kim Kardashian and US TV personality Ryan Seacrest, logged off their computers last week to mark World AIDS Day, and refused to return to tweeting and updating their Facebook pages until the target of $1 million was reached.