Tyra Banks thinks Britney Spears should "kill herself", it has been reported.

The outspoken talk show host was overheard saying Britney - who recently released her comeback album Blackout - should follow in the footsteps of Marilyn Monroe and end her life by taking a drugs overdose.

A shocked onlooker said: "Tyra was saying, really loudly, 'Britney should just go ahead and kill herself after the album and go out like Marilyn, very grand. She should have done it after the last album.'

"It was terrible, nobody could believe she was saying it, let alone saying it without caring who heard!"

A representative for America's Next Top Model host Tyra denied the claims, saying: "This is absolutely not true."

Meanwhile, Tyra has herself been on the receiving end of some harsh criticism recently, after America's Next Top Model judge Janice Dickinson labelled her "fat" on TV.

Speaking on US show TODAY Janice said: "You want to see someone who's fat? I'm sorry, Tyra. Tyra Banks is fat."

Later, Janice appeared on evening show Access Hollywood to explain her comments.

She said: "She's large. She admits herself that she has a fat blank, blank, blank, referring to her derriere - she publicly admits it.

"I'm not criticising Tyra, I was not criticising her. It's the truth. She publicly claims she loves to get down on a bunch of waffles. Ms. Banks is a wonderful lady and this is a big brouhaha over nothing."