Sharon Osbourne believes Justin Bieber is ''lost''.

The 'Talk' co-host has slammed the 19-year-old singer's new bad boy persona, claiming he is ''about as mean as a f***ing kitten''.

She told The Daily Beast: ''I feel really bad for him. There's this little kid with a huge dream, he's cute, girls love him, and he wants to be a mean boy, and he's about as mean as a f***ing kitten, and he's trying to act out. It's like p***ing in a bucket. It's like, 'Oh, we're the bad boys!' F**k off! You don't know what bad is

''And I think that he's lost, I really do. I think he doesn't understand he's white and not black, that's a huge problem. And, at the point he's at in his career, it's so dangerous because we've seen it all before a million times. Where do you go when you're a child entertainer and then you want to transition to be a man? Very few make it.''

Sharon also lashed out at Kanye West, calling the 36-year-old rapper ''an average-looking man with an average talent''.

She said: ''I have no time for him. He bores me. I said it on the show, he's an average-looking man with an average talent, but he's a great salesman. He should sell cars because they would f***ing fly out the door. He's his number one fan.''