One Direction, Ed Sheeran and Elbow are among the acts who will take part in a fourth version of the Band Aid charity single, Do They Know It's Christmas.
Announcing the project, Bob Geldof and Midge Ure said the song's lyrics would be changed to reflect the Ebola crisis.
The original was released in 1984. It sold 3.7 million copies and raised £8m for famine relief in Ethiopia.
The new version will be recorded this Saturday and should be available for download on Monday morning.
Geldof and Ure, who masterminded the first version, said the project was nothing to do with nostalgia.
"We should gather the pop crowd together to do our thing," said Ure at a press conference on Monday.
So far, confirmed artists include U2's Bono, Chris Martin of Coldplay, Emeli Sande, Underworld, Sinead O'Connor, Paloma Faith, Foals and Bastille, who have given up two arena dates to record their contribution.
Versions will also be recorded in France, Germany and the US. "Think Daft Punk. Think Johnny Hallyday," said Geldof.
The money raised will go towards the fight against Ebola in West Africa.
The original track featured the voices of George Michael, Bono, Duran Duran and Bananarama, among others.
The single was the catalyst for the cross-continent Live Aid concerts in London and Philadelphia, which raised more than £40m.
The 1989 incarnation of Band Aid was produced by the Stock, Aitken and Waterman stable, largely featuring their artists such as Kylie Minogue, Jason Donovan and Sonia.
Band Aid 20, marking 20 years of the record, included the likes of Coldplay, Dizzee Rascal, Ms Dynamite, Will Young and Robbie Williams.
Bono, Sir Paul McCartney and George Michael returned for the collaboration, which was released to raise money for Sudan's troubled Darfur region.
Should be interesting to see how they're gonna change the song. They better not ruin it!