Thousands of Harry Potter fans have signed a petition pleading for J.K. Rowling to keep writing novels about the wizard-in-training as the seventh and final book comes out in July.

The "Save Harry!" petition was launched by British book chain Waterstones on Monday.

JK Rowling, seen here at the European premiere of the movie Harry Potter And The Order Of The Phoenix, has said the seventh book will be the final one.JK Rowling, seen here at the European premiere of the movie Harry Potter And The Order Of The Phoenix, has said the seventh book will be the final one.
(Ian West/Associated Press)

"Millions, perhaps billions of us, love reading his adventures and we never want them to end," says the website.

Harry Potter and the Deathly Hallows is due out July 21.  Amazon says the book is the most pre-ordered item ever, with 1.6 million in pre-sales.

Rowling, who spent 17 years writing the series, has said two main characters will die but would not divulge if the main character passes away.

She also revealed that she shed tears when she finished writing the last instalment of the series, which has sold 325 million copies world wide.

The author gave fans a glimpse into her own inner struggle to end the series during a weekend interview broadcast on BBC Radio.

"I think that Harry's story comes to quite a clear end in Book 7," she said." But I have always said that I wouldn't say never. I can't say I will never write another book about that world, just because I think: 'What do I know, in 10 years' time I might want to return to it'. But I think it is unlikely."

Wayne Winstone, head of children's books at Waterstones, said fictional characters can always be resurrected.

"Sir Arthur Conan Doyle famously killed off Sherlock Holmes, yet brought him back after years of demand from his fans and publishers. Couldn't the same happen for Harry Potter? "

Winstone says he's hoping to get at least a million signatures.

The latest film in the series, The Order of the Phoenix, opens around the world on July 11.