Katy Perry, Brie Larson and Ellen DeGeneres also expressed their outrage on social media.
Beyoncé is offering transgender students her support.
The pregnant singer took to Facebook on Thursday to speak out against President Donald J. Trump's decision to withdraw protections for transgender students in public schools, encouraging others to "protect trans youth."
The guidance, which was instated by former President Barack Obama under Title IX protections last May, let transgender students use bathrooms and locker rooms corresponding with their gender identity, and threatened to withhold federal funding for schools that did not comply. Trump rescinded the guidelines on Wednesday, arguing that states and public schools should have the authority to make their own decisions without federal interference.
"#LGBTQ students need to know we support them. Share your support to #protecttransyouth at glsen.org/100days & put #KindnessInAction GLSEN," Beyonce wrote.
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Jackie Evancho, who performed at Trump's inauguration, expressed her disappointment on Twitter, and asked to meet with Trump in person to discuss the issue. Evancho's sister, Juliet, is transgender.
White House spokesman Sean Spicer said in a press conference that the administration was pressed to act in response to the pending Supreme Court case, G.G. vs. Gloucester County School Board. The case pit a Virginia transgender boy, Gavin Grimm, against school officials who want to deny him the use of the boys restroom at his high school.
Stars like Katy Perry, Laverne Cox, and Brie Larson were quick to speak out on the issue and lend their support to Grimm and other transgender students, using the hashtag "#StandwithGavin."
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See more celebrity tweets in opposition to Trump's decision below:
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