A new version of the Band Aid charity single has been recorded by stars including One Direction, Emeli Sande, Rita Ora and Ed Sheeran in a studio in London.
Ellie Goulding, Sam Smith, Chris Martin and Bono also sang on the reworked Do They Know It’s Christmas?.
The recording, which comes 30 years after the original Band Aid, will raise money for the fight against Ebola.
The UK government has agreed to waive VAT on the single.
Organizer Bob Geldof, who also masterminded the original in 1984, said he addressed the participants “like the headmaster” before they sang the chorus.
The song’s first lines have been recorded by One Direction. It will get its first play on ITV’s X Factor results show on November 16.
Other artists taking part included Elbow, Seal, Jessie Ware, Fuse ODG, Sinead O’Connor, Angelique Kidjo, Olly Murs, Paloma Faith, Queen drummer Roger Taylor, Clean Bandit and Foals.
Rita Ora was the first to record her lines and left early.
Ed Sheeran flew in from his tour in Germany, while Bastille cancelled two US arena gigs to be involved. Disclosure and Underworld were also in the studio to do remixes.
Saturday’s recording session took place at the Sarm studios in west London, the venue where stars such as Wham!, Duran Duran, Sting and Status Quo recorded the original.
That single raised £8 million ($13 million) for famine relief in 1984. This time, the lyrics have been rewritten.
Instead of the line “Where the only water flowing is the bitter sting of tears”, the new version has the line “Where a kiss of love can kill you and there’s death in every tear”.
Bono’s famous line “Well tonight thank God it’s them instead of you” has been changed to “Well tonight we’re reaching out and touching you”.
The music video will be edited in “record time” so it can be shown on The X Factor at 20:00 GMT on November 16.
The song will be made available to download at 08:00 GMT on November 17, priced 99p ($1.5). A CD version costing £4 ($6) will be released three weeks later with a cover designed by artist Tracey Emin.
The track will not be made available on Spotify and other music streaming services until January.
Bob Geldof told fans: “Come Monday at 08:00 when every station plays this track across the nation, buy this thing. Don’t go looking for it free. Buy it.”
The original version sold 3.7 million copies. Five years later, another version was produced by Stock, Aitken and Waterman, largely featuring their artists such as Kylie Minogue, Jason Donovan and Sonia.
In 2004, Band Aid 20 was recorded by the likes of Coldplay, Dizzee Rascal, Ms Dynamite, Will Young and Robbie Williams.