The giveaway begins today (11 January) and comes ahead of a new expected TV campaign by Leo Burnett, which rolls out in February.
McDonald's has secured a deal with book publisher HarperCollins, owned by Rupert Murdoch's News Corporation, to give away millions of copies of Morpurgo's 'Mudpuddle Farm' children’s books with Happy Meal purchases.
Murpugo is the author of 'War Horse', which has been made into a film by Steven Spielberg and launches in cinemas this weekend.
The McDonald's campaign is supported by the National Literary Trust, as well as Jade Goody's ex-boyfriend Jeff Brazier, who is acting as an ambassador for the campaign.
In total, six titles from HarperCollin's 'Mudpuddle Farm' range will be made available during the promotion.
The move could come in for criticism from some quarters, who will argue McDonald's is offering sweeteners for parents and children to buy Happy Meals.
Jonathan Douglas, director of the National Literacy Trust, said: "We are very supportive of McDonald's decision to give families access to popular books, as its size and scale will be a huge leap towards encouraging more families to read together."
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