Allen joined Rodrigo onstage at the Glastonbury Festival in England over the weekend, for a duet of her 2009 anthem.
Olivia Rodrigo and Lily Allen are sticking it to the Supreme Court following their reversal of Roe V. Wade Friday, which struck down the landmark 1973 ruling which protects a person's right to an abortion.
Allen joined Rodrigo onstage for day four of the Glastonbury Festival in England Saturday, where she performed a very special rendition of her 2009 anthem "F**K You."
After introducing Allen, who said she originally wrote "F*** You" with former President George W. Bush in mind, the 19-year-old spoke out against Friday's ruling.
"I'm devastated and terrified that so many women and so many girls are going to die because of this," Rodrigo. "I wanted to dedicate this next song to the five members of the Supreme Court who have showed us that at the end of the day, they truly don't give a s**t about freedom."
Rodrigo then proceeded to name the five justices who ruled to overturn Roe v. Wade, with Chief Justice John Roberts delivering a concurring opinion, writing that while he agrees that the viability line established under Roe should be discarded and Mississippi's law upheld, Roe and Casey should be left untouched.
"This song goes out to the justices Samuel Alito, Clarence Thomas, Neil Gorsuch, Amy Coney Barrett and Brett Kavanaugh," the "drivers license" singer said to the cheering crowd. "We hate you."
Allen posted about the powerful performance on Instagram, calling the moment an emotional one. While she marveled at her daughters being able to watch her onstage alongside their favorite pop star, she wasn't sure this day would come, looking back on her journey to sobriety and her break from the stage.
"Quite emosh. Things are truly messed up, but at least my babies got to see their mamma play and slay Glastonbury with their favourite pop star. They were very proud and so was I. I didn’t know whether i’d be able to get up on a stage like that sober again if i’m honest, a part of me thought it was all in the past," the 37-year-old singer wrote before adding that she may not be hanging up her mic just yet. "I had the most amazing day. Thanks @oliviarodrigo for having us. You smashed your first Glastonbury. Who knows, maybe i won’t hang up my 🎤 just yet. 😜."
The 20-year-old singer continued, "I'm just going to say that because I can't bear to think about it any longer."
Eilish then dedicated her song "Your Power," which is about abuse by older men, to those affected by Roe's reversal.
See more of their reactions below.