Rod Stewart, Michael Buble and X-Factor alumni Leona Lewis and JLS have all agreed to take part in the Haiti charity single.
Simon Cowell is organising the recording, a cover of REM's Everybody Hurts.
According to The Sun newspaper, Robbie Williams, Coldplay, Take That and Sir Paul McCartney have also been approached.
The proceeds from the single, which is being organised by Cowell, will be split between the Disasters Emergency Committee (DEC) and the Sun's Helping Haiti campaign.
Meanwhile, George Clooney is planning a fundraising Hope For Haiti telethon, with artists including Madonna, Beyonce, Jay-Z, Rihanna, Bruce Springsteen, Jennifer Hudson, Mary J Blige, Shakira and Sting.
An estimated 1.5 million people were left homeless by the 7.0-magnitude quake, which is believed to killed as many as 200,000.
At least 75,000 bodies have so far been buried in mass graves, the government has said. Many more remain uncollected in the streets.
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