Single mother and actress Michelle Williams has revealed during the Cannes Festival that motherhood is "at the centre of everything I do". The star was speaking at a press conference for her new film Wonderstruck - in which she plays a mum - and revealed being a mother effects "every choice" she makes.

Michelle WilliamsMichelle Williams puts motherhood at the centre of everything she does

The film, which had its first screening at Cannes on Thursday, is a black and white silent movie.

Wonderstruck has dual narratives, set in 1927 and 1977, telling the stories of a young deaf girl, Rose, and Ben, a 12-year-old living 50 years later, and how their lives connect in ways that only become clear at the end.

Williams related the Mother's Day card message she received from daughter Matilda, saying it speaks to what she tries to achieve as a parent.

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The card said: "Mom, thanks for letting me be me".

The 36-year-old actress is mother to 11-year-old daughter Matilda, who she gave birth to during her relationship with late actor, Heath Ledger.

The pair ended their three-year relationship in September 2007 and tragically Heath died from an accidental overdose in January 2008.

She has since raised their daughter alone - ended a brief relationship with Spike Jonze because the timing of their relationship was "impossible".

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The actress said she had the same attitude towards the actors at the centre of Wonderstruck, saying: "What I find most interesting about motherhood in this film is being responsive to the child, to the child you're parenting personally and professionally."

Williams, who was nominated for an Oscar for Manchester by the Sea, said: "There is no area of my life it leaves untouched. Every choice I make in the films I do, every choice I make about what we have for breakfast in the morning - but I think it's what becoming a parent does to you."

Williams stars alongside Julianne Moore in the film which is directed by Todd Haynes with Millicent Simmonds starring as young girl Rose.

It is her first film, with Haynes having sought to fill the role from the deaf community.