And it's looking quite promising!
"It's amazing these great singers are clearing their schedules to make this happen," said Simon. "I just found out Mariah has changed her schedule to be able to do this too."
The recording began this weekend with Cheryl Cole and British band JLS, but others expected to get into the studio are Take That, Michael Bublé, Westlife, Alexandra Burke, James Morrison, Mika and James Blunt.
"It says such a lot that everyone is working so hard to help Haiti," he continued. "This is something that really matters to us all, and I'm so grateful for the support we are getting."
Can't wait to hear it!
[Image via WENN.]