The "I Kissed A Girl" singer, speaking with Australia's Ash, Kip & Luttsy on Nova FM, worked with the Rolling Stones frontman on his 2004 single "Old Habits Die Hard" (from the movie Alfie), doing background vocals prior to her career breakout.
"I was 19 maybe, I did a lot of stuff behind the scenes," she said, adding that at the time, she also worked on a Miley Cyrus album.
"I actually went to dinner with Jagger one time, and he hit on me when I was like 18!" she said. "That was a long time ago, and he's been very kind."
One of the hosts asked Katy, "How you turn him down? How do you turn down a legend like Mick Jagger?"
"Well you bring a friend and then they do them!" Perry said. "You sacrifice your friend!"
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