Curtis will direct the film, about 'Winnie the Pooh' creator A A Milne and the relationship between him and his son Robin.
Robin, who initially had a difficult relationship with his father, served as the inspiration for the character of Christopher Robin.
Pooh was named after Robin's teddy bear. The real Robin's toys also lent their names to other Winnie the Pooh characters such as Tigger, Eeyore and Piglet, reported Variety.
Robbie is in negotiations to play Milne's wife.