The "Closer" singer has written songs for several big music stars including, Leona Lewis, John Legend, Estelle, Usher and Pussycat Dolls, and hasn't ruled out collaborating with the British duo.
He said: "LA Reid introduced me to Duffy's record. I really love her voice. You guys have a lot of talent."
The 25-year-old has also spoken highly of Amy, and insists it is her turbulent personal life that makes her music so great.
He added to Britain's Daily Star newspaper: "I'm a die-hard fan. Self-destructiveness is what makes her real - it makes for great songs."
The singer-songwriter penned "I'm You" for the US version of Leona's hit album "Spirit," and is thrilled she has made it Stateside with his help.
He said: "Her talent will carry her in the US but maybe me being so hot helped. Leona is a beautiful person inside and out. She's not just a pretty face - her voice is undeniable."
Last month, Leona became the first British solo artist to top the US album charts with a debut record.
Her single "Bleeding Love" also topped The Billboard Hot 100 chart.
