London, Apr 18 (IANS): "Harry Potter" author J.K. Rowling is a woman of her words. She had promised fans an encyclopaedia on her popular series, and has now revealed it is already underway.

"For a long time, I have been promising an encyclopaedia of Harry's world, and I have started work on it. It is likely to be a time-consuming job, but when finished I shall donate all royalties to charity," Rowling stated on her website, according to contactmusic.com.

Rowling has no plans to write another "Harry Potter" book.

"I have no immediate plans to write another Harry Potter novel, and I do think that I have rounded off Harry's story in the seven published books," said the author, whose books were turned into a successful film franchise.

Rowling's next novel -- "The Casual Vacancy", will be published later in 2012.

Its story revolves around a small parish town named Pagford, a quintessential English dwelling with a cobbled market square and an ancient abbey.