Amanda Seyfried is a Justin Timberlake fan

Amanda Seyfried loves Justin Timberlake's "beautiful" singing.

The pair star together in new movie 'Now' and the actress says her most enjoyable part of shooting was listing to the singer-and-actor during breaks from filming.

She said: "The best part was when Justin kept bursting into song on set. He'd just be mocking something but it'd sound beautiful. God, I love it when he opens his mouth that way."

While Amanda loved hearing Justin exercise his vocal talents, she has no plans to show off her own again, insisting there will not be a sequel to musical movie 'Mamma Mia!'.

She explained Total Film magazine: "It is just not happening. And if it does, I honestly don't thing they could make something good. I don't see the point in trying to stop it because 'Mamma Mia!' was so sweet and positive and people love it - to try and do it again would be a big mistake."