Author Julia Donaldson is to team up with illustrator Axel Scheffle to release the first new Gruffalo book in over two decades. The pair have previously teamed up on the award-winning Gruffalo (1999) and the 2004 follow-up The Gruffalo’s Child. The brand-new as-yet-untitled story is set to release next year.

Publisher Macmillan Children’s Books described the stories as a “bestselling phenomenon”. Julia’s books have sold almost 50 million copies, with the Gruffalo accounting for three million, having been translated into 113 languages. The Sussex-based author admits writing a follow-up story can be difficult. But she hopes the new story will resonate with audiences as much as the first two Gruffalo tales.

Speaking to The Bookseller, Julia said: “It’s always a challenge to write a sequel. Five years elapsed between publication of The Gruffalo and The Gruffalo’s Child, and now it will be more than 20 between The Gruffalo’s Child and the third book. I actually had the basic idea for the story a long time ago, but couldn’t think how to develop it.

“I was of course delighted when Axel came on board, and am even more so now that I’ve seen the brilliant sketches he’s already done for the new book. I really hope that children – and adults too – will enjoy the new story, as I know what a wonderful experience shared reading can be.”

The publisher added: “Macmillan Children’s Books is thrilled to be publishing this extraordinary new story, which sees the return of much-loved characters in a fresh and exciting adventure that has all the hallmarks of a Julia Donaldson and Axel Scheffler classic.

“The team at Macmillan plans for this highly anticipated publication to be one of the biggest in its history, supported by a blockbuster marketing and publicity campaign.”

The new book will be used by the National Literacy Trust as it looks to encourage childhood reading. It came after the charity found only one in three children enjoy reading in their spare time, the lowest level since 2005, it claims.

Julia added: “It was only when the NLT, whose work I’m very impressed by, used the first two books as part of their Early Words Matter programme that I was spurred on to get my idea out of the cupboard and see once and for all if I could turn it into a really satisfying story.”

Axel admits he had remained coy on the idea of another Gruffalo book, but when Julia sent him the text, decided to pick up his pen once more. Speaking to The Bookseller, he added: “As I have had to draw the odd Gruffalo and his daughter over the past 20 years, I’m not completely out of practice.”