Published Wednesday, 22 August 2012
The Smile hitmaker insisted she had retired from performing in 2009 to focus on motherhood, but announced earlier this year that she was back in the studio working on new material.
Pink persuaded the pregnant pop star to appear on her new track True Love, and invited Allen to jet to the US on Monday to make an appearance at her intimate show for TV series VH1 Storytellers.
Allen tells The Sun, "It was great, felt strange being back on stage again but Pink made me feel at ease. Really enjoyed myself though. Can't wait to get back out there."
Pink thanked the singer publicly on Twitter, writing: "I filmed VH1 Storytellers last night - dream come true performance. Thanks Lily Rose Cooper... for joining me!!!!"
Allen made her live comeback in June by making a cameo appearance onstage with rapper Professor Green at a Stone Roses concert in Manchester, England.