The one-hour September 12 special — to be broadcast on all four US networks and livestreamed on social media platforms — will urge donations to aid groups working in the aftermath of the disaster.
Beyonce — a native of hard-hit Houston who has vowed a generous response — will be making her first public appearance since giving birth to twins in June.
Dubbed “Hand in Hand,” the telethon will also feature performances, appearances or taped messages by Hollywood A-listers Clooney, Matthew McConaughey, Julia Roberts, Adam Sandler and Reese Witherspoon.
Also scheduled to appear are singing great Barbra Streisand and talk-show titan Oprah Winfrey.
The special will take place in Los Angeles with stages in New York and Nashville, as well as a performance by Texas country music star George Strait as part of a charity concert in San Antonio.
Celebrities have been opening up their wallets to support relief after the historic storm.
Folk legend Paul Simon and his wife, fellow singer Edie Brickell, said over the weekend that they would give $1 million and focus on smaller communities outside of Houston.
The amount matched a $1 million pledge by leading Hollywood star Sandra Bullock, who maintains homes in nearby Houston and New Orleans.
Punk rockers Green Day put up $100,000 and on Tuesday began a livestreamed show over Facebook, encouraging viewers to chip in to AmeriCares — a non-governmental aid group that provides emergency health care both in the United States and overseas.
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