Amy Winehouse and Pete Doherty may not be making beautiful music together any time soon after the Rehab singer reportedly branded her fellow skank’s songs “shit.”

Despite being more or less joined at the hip this week, the pair have failed to hit it off musically, it's claimed.

A source told the U.K.'s Mirror, "Amy has thrown back every song Pete has written for her.

"She keeps telling him it's rubbish - and worse - and she'll only perform if the song is great.

"When she's in the studio she can be ruthless and doesn't care about hurting people.

"Pete's really struggling to get it together. It hasn't clicked yet."