Paul McCartney is writing a picture book about a magical grandad.

Hey Grandude! is about a magical grandfather and his four grandchildren, and is described by its publishers as both a heartwarming family story and an adventure tale with a twist of magic.

The former Beatle said: “I’ve got eight grandchildren and they’re all beautiful and one day one of them said to me “Hey Grandude!”. I said “What?” and I thought, I kind of like that, so from then on I was kind of known as Grandude.

“So I thought, you know what, it’s actually a nice idea for a book, so I started to write some stories, and then I talked to the book publishers and they liked what I was doing.

The book will be illustrated by Kathryn Durst and published in September 2019.