"The Haitian people need our help. They need to know they're not alone, they need to know that we still care."
Clooney then introduced the audience to a host of stars manning telephones in the Los Angeles studio, including Ben Affleck, Daniel Day-Lewis, Mel Gibson, Colin Farrell, Meg Ryan and Ringo Starr.
Friday's event is split between Los Angeles and New York, where Wyclef Jean is hosting.
Those who wish to donate can do so by visiting Hopeforhaitinow.org.