An eighth Harry Potter book is to be released this summer - containing the script for a new stage play telling the wizard's story.

A hardback edition of Harry Potter and the Cursed Child - Parts I & II will be released on 31 July, the day after the play has debuted on stage.

It sees Harry as a father and an overworked Ministry of Magic employee.

The play is from an original new story by JK Rowling, Jack Thorne and John Tiffany.

Harry Potter and the Cursed Child will tell the "untold part" of the boy wizard's story, including the story of the lives of his murdered parents, Rowling has said.

It will pick up the story 19 years after Harry was last seen in Harry Potter and the Deathly Hallows, waving his two eldest children off to Hogwarts.

Fan appeals

The script's ebook will be published simultaneously with the print editions.

David Shelley, chief executive of the publishers Little, Brown Book Group said: "We are so thrilled to be publishing the script of Harry Potter and the Cursed Child.

"JK Rowling and her team have received a huge number of appeals from fans who can't be in London to see the play and who would like to read the play in book format - and so we are absolutely delighted to be able to make it available for them."

The special rehearsal edition of the script book will comprise the version of the play early in the production's preview period and is therefore subject to being changed before the official opening.

Previews of Harry Potter and the Cursed Child begin in May at London's Palace Theatre, with both plays set to open on 30 July. The hardback and ebook will go on sale at 0001 on 31 July.

Jamie Parker, currently starring in the West End show Guys and Dolls, will star as an adult Harry in the production.

Noma Dumezweni, known for her 2006 Olivier Award-winning role in A Raisin in the Sun and for stepping in at the last minute to replace Kim Cattrall in Linda at the Royal Court, will play Hermione Granger.

London Road star Paul Thornley will play Ron Weasley.

The play was first announced in December 2013, after the author said she had "received countless approaches" over the years "about turning Harry Potter into a theatrical production".