The Duke of Cambridge is a karaoke king with "star quality", American pop star Taylor Swift said in an interview.
William shared a microphone with country singer Swift, 24, as the pair joined Jon Bon Jovi on stage for a rendition of Livin' On A Prayer at a charity function last year.
Footage of the unlikely collaboration at Kensington Palace went viral after the duo were beckoned on stage to belt out the rock classic.
Swift, who has enjoyed UK chart success with We Are Never Getting Back Together, said the royal possessed surprising vocal qualities.
She told the Mail on Sunday's Event magazine: "Both of us were more screaming than singing.
"But even through all that I could hear his voice and it is pretty good. A nice tone.
"I'd definitely say he's got star quality, and if he ever wants me to sing with him again, I'll be there."
The Stateside singer, previously romantically linked with pop stars including One Direction's Harry Styles, described how William was initially reluctant to join the veteran rocker on stage.
She said the frontman jokingly enlisted the audience to "put pressure" on the royal to sing.
Swift, who is in England to play several dates at London's O2 Arena, said: "Prince William looked at me and said, 'I'll do it if you do it too', and then he took my hand.
"I was surprised and flattered and it felt surreal and completely natural at the same time.
"We jumped on the stage and started to sing and then we were really yelling.
"I still can't believe I've sung with Prince William."