We all have certain friends that we know we can turn to when times get tough. For Katy Perry, that friend is Sia.

Perry has praised the enigmatic Australian singer-songwriter in a new interview, in which she thanked her “best friend” for supporting her through “some difficult times” – particularly the aftermath of the US election.

The two women worked together on the lyrics for Perry’s new single, Chained to the Rhythm. However, Perry told Capital FM’s Roman Kemp that the duo have “always kind of written” songs together, including on Perry’s 2013 album Prism.

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“I’ve known her for years,” she said. “I’ve known her my whole career in the spotlight, and we’ve seen each other at all these places and gone through ups and downs.

“She’s one of my best friends and she’s helped me through some difficult times,” Perry continued.

Perry, who was a dedicated supporter of Hillary Clinton during the US election campaign, added that writing music with Sia had helped her shake off the post-election blues.

“After the election… I was kind of depressed,” she said. “You know, I definitely didn’t want to write a club banger. I was like, ‘How are we writing a club banger when the world is on fire?’”

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On first listen, the song she and Sia ended up writing, Chained to the Rhythm, does indeed sound like a typical “club banger”. However, the lyrics reveal Perry taking a more openly political stance than she has done in previous songs, with lines alluding to fake news, social media echo chambers and America’s fractured political landscape.

A guest verse from rapper Skip Marley (grandson of Bob), meanwhile, states that “time is ticking for the empire”, adding: “We’re about to riot… They woke up the lions”.

Perry told Capital FM that writing Chained to the Rhythm was “a nice exercise of writing a song that at first listen is a really fun song, but I guess the more you dive in to it, it has a different sub-text.”

Playing with political subtext looks set to be a theme in Perry’s new album. When she performed Chained to the Rhythm at the 2017 Grammy’s, even her stage costume was packed with political references – from the feminist movement to Hillary Clinton and Planned Parenthood.

Images: Rex Features