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Hollywood’s most glamorous activists are throwing their weight behind the March for Our Lives, a movement started by the survivors of the Florida school shooting.

Famous names including Justin Bieber, Lady Gaga, Amy Schumer and Cher have voiced their support for the action to prevent gun violence, with Oprah, the Clooneys and Steven Spielberg promising donations of $500,000 each.

“Cameron good talking to you last night. All of your bravery is amazing. I stand with you guys,” Bieber tweeted Cameron Kasky, the 17-year-old student from Marjory Stoneman Douglas High who created the #NeverAgain hashtag and Facebook page after 17 people were shot dead at his school in Parkland, Fla.

George Clooney started the financial ball rolling on Tuesday, announcing in a statement that he and Amal were “so inspired by the courage and eloquence” of the Florida students. The activist couple promised to attend the March 24 rally and make a donation in the names of the couple’s 8-month-old twins, Alexander and Ella.

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FILE PHOTO: Director George Clooney and his wife Amal attend the premiere for "Suburbicon" in Los Angeles, California, U.S., October 22, 2017. REUTERS/Mario Anzuoni/File Photo - RC1F66B9B3A0 (Reuters)

Hours later, film producer Jeffrey Katzenberg and wife Marilyn said they would donate the same amount, calling the students “brave young leaders” who have “taken their pain and grief and turned it into action.”

Director Steven Spielberg said the students in Florida and across the country were “demonstrating their leadership with a confidence and maturity that belies their ages,” promising he and wife Kate would also put in $500,000.

Oprah Winfrey said the young people reminded her of “the Freedom Riders of the 60s who also said we’ve had ENOUGH and our voices will be heard,” vowing she too would match the Clooneys’ donation.

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(AP)

Gaga said she was “speechless at their courage” and “proud that these kids and young adults are our future”, while Schumer exhorted her Twitter followers to “demand that lawmakers do their jobs and take action to prevent gun violence.”

In a tweet almost entirely in capitals and littered with exclamation marks, Cher said she believed the movement could scare Congress into action, adding “KIDS CAN BE CATALYSTS 4 CHANGE.”

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