LONDON: British author J K Rowling has announced that the seventh and final book in her wizard saga will be called Harry Potter and the Deathly Hallows.

But fans of the series that has already sold an estimated 300 million copies worldwide were kept guessing - the publication date has not been set.

The intriguing and ominous title had Potter aficionados puzzling over what might happen to the bespectacled hero.

"Will a favourite character die? Could Harry himself face a grisly demise? How will it all end?" asked Sam Harrison, children's buyer at the British bookchain Waterstone's.

"But surely the question all Potter fans will want answering as soon as possible is - when can they get their hands on a copy?" he said.

Rowling, whose creation has turned her into one of the world's richest and most successful authors, revealed on her website this week "I'm now writing scenes that have been planned, in some cases, for a dozen years or even more."

"I am alternately elated and overwrought. I both want, and don't want, to finish this book (don't worry, I will)".

She said in the diary entry on her official website that Potter had now inveigled his way into her dreams.

"For years now, people have asked me whether I ever dream that I am 'in' Harry's world," Rowling wrote. "The answer was 'no' until a few nights ago when I had an epic dream in which I was, simultaneously, Harry and the narrator."

But she gave no clues as to what will happen at the end of the upcoming book, amid speculation that some of the characters, possibly Harry himself, will die.

The Potter books have a huge influence on the financial results of their US and British publishers, Scholastic and Bloomsbury.

Though it published the paperback edition of the sixth book this year, Bloomsbury warned on Dec. 11 that profits could widely miss analysts' forecasts because of sluggish pre-Christmas book sales and other factors.

This wiped out nearly one-third of its market capitalisation.

Kyle Good, spokeswoman for Rowling's US publisher Scholastic Corp., said they had not received a date for when they would receive the manuscript nor when the book would be published.

Rowling's last novel, Harry Potter and the Half-Blood Prince, was her most successful book in the US, she said, selling 6.9 million copies in the first 24 hours.