War Horse author: 'People must remember the background'

Speaking at the UK premiere of War Horse, author Michael Morpurgo told the BBC that the success of his book was down to "luck".

He said: "My book sat on everyone's back shelves, not being read for 25 years.

"Then the National Theatre comes along and makes a play of it with puppets, and it's just this wonderful iconic production," he added.

Morpurgo said he was conscious that he trod softly on the memories of people who lost family during the war and that despite a happy storyline it was important that people remember the background.