Charlie Puth has recorded a song for Alicia Keys.

Charlie Puth

Charlie Puth

The 'See You Again' hitmaker got into the studio with his fellow 'The Voice US' mentor to work on the track and said it was one of the "most special songwriting sessions" he's ever had.

Asked about the song, he told PopSugar: "The song is for Alicia, but I have to respect the art and not give too much away, because we only want to show the finished product. I will say, though, that it was one of the most special songwriting sessions I've ever had. It was a very humanistic process. It didn't feel like record labels put us together. She's just a people person and it made me feel really comfortable working with a superstar. And I think we wrote a superstar song."

Meanwhile, the 24-year-old pop hunk - who teamed up with Selena Gomez on 'We Don't Talk Anymore' - has said he'd love to work with John Mayer in the future.

He said: "I would love to collaborate with John Mayer, who I got the pleasure of meeting a couple months ago. I think he's fantastic. He's another Berkeley cat. We stayed in the same dorm room -- shout-out to 737 -- so immediately we had something to talk about.

"And I just love his chord changes and his knowledge of what goes into a record. That was his major at Berkeley and that's what I studied as well, so we have a lot in common."