Kevin Mazur/Getty Images for Global CitizenStevie Wonder is among the celebrities speaking out in response to President Donald Trump‘s criticism of NFL players who kneel in protest during the national anthem.

“Tonight, I’m taking a knee for America. But not just one knee, I’m taking both knees,” Wonder, 67, said onstage while performing at the Global Citizen Festival in New York City on Saturday. “Both knees in prayer for our planet, our future, our leaders of the world and our globe.”

His comments came the day after the president sparked controversy by declaring at a rally in Alabama that NFL team owners should fire players who kneel in protest to highlight social issues. He continued his criticism on Twitter on Saturday.

“If a player wants the privilege of making millions of dollars in the NFL, or other leagues, he or she should not be allowed to disrespect,” he began, continuing in a followup tweet, “Our Great American Flag (or Country) and should stand for the National Anthem. If not, YOU’RE FIRED. Find something else to do!”

On Sunday, Mr. Trump turned his attention to football fans, saying that if fans were to stay away from games “until players stop disrespecting our Flag & Country, you will see change take place fast. Fire or suspend!”

Other celebrities responding to the president’s comments included Harry Potter author J.K. Rowling, Grey’s Anatomy star Jesse Williams, Modern Family actor Jesse Tyler Ferguson and John Legend, who tweeted, “Trump thrives on division and chaos. He wants to pit us against each other because he thinks his side can win (w/voter suppression, etc.).”

“We have to show him that we can bring a multiracial coalition together for justice and equality for all. Let’s unite around that,” he concluded.

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