Michelle Williams feels like a ''baby'' at 'Cabaret' rehearsals.

The 33-year-old actress is to make her Broadway debut in a revival of the production - in which she will play 19-year-old Sally Bowles - and admits she has needed extra preparation time ahead of the production's opening next month.

She said: ''They were generous enough to start me a few months before everyone else. I've been taking classes in a studio in Brooklyn and I'm basically being a kid there. I feel like a baby. I get to rehearsal, and I'm like, 'What do I do?' ''

The 'My Week with Marilyn' actress also joked about her ''bravery'' in taking on the role in the musical, which sees her star opposite Alan Cumming.

Speaking at a TimesTalk discussion with her co-star and director Rob Marshall at New York's TimesCenter on Monday (24.02.14), she said: ''Some people call it bravery, but really, I call it my inability to see a decision through to the end when I say 'yes.' ''

The production - which will run for 24 weeks - previews from March 21 ahead of the official opening night on April 24.