“F*** America. I’m f*****g renouncing my citizenship. I’m f*****g coming here,” Armstrong told a crowd at the band’s show in London on Friday, just hours after the Supreme Court announced its decision. “I have just had too much…stupid in the world to go back to that miserable f*****g excuse for a country.”

It’s unclear whether Armstrong will go through with his plans to renounce his U.S. citizenship, though he followed up his comments by telling the London crowd he was serious. 

“I’m not kidding. You’re going to get a lot of me in the coming days,” Armstrong told the crowd.

Neither Armstrong nor representatives for Green Day immediately responded to Fortune’s request for comment.

Since the opinion was published, several states have already activated abortion bans via “trigger laws,” and several others are expected to follow suit in the coming weeks and months. 

Armstrong, 50, is one of a number of musicians who have taken to the stage to announce their anger at the Court’s decision, which overturned the 50-year old court ruling that established abortion as a constitutional right.

At the U.K.’s Glastonbury Festival, several U.S. musicians, including Billie Eilish, Olivia Rodrigo, Megan Thee Stallion, Phoebe Bridgers, and Kendrick Lamar expressed their disappointment and shock at the decision. 

Eilish told the crowd during her headlining set it was “a really, really dark day for women in the U.S.” Rodrigo brought out British singer Lily Allen during her set to perform Allen’s song “F*** You,” which Rodrigo dedicated to the Supreme Court justices who voted in favor of overturning Roe. 

Bridgers led a “F*** the Supreme Court” chant during her performance. Lamar closed out his set chanting “Godspeed for women’s rights,” and Megan Thee Stallion called out her home state of Texas for banning abortions. 

This is not the first time that Armstrong and Green Day have taken aim at conservative U.S. politics and policy, both on stage and through their music. 

In 2016, during a performance at the American Music Awards, the band started a “No Trump, no KKK, no fascist USA” chant. In 2004, the band released the album American Idiot, which took aim at the Iraq War and post-9/11 America.