Harry Potter and the belated delivery

JK Rowling is still writing the long-awaited fifth Harry Potter book - dashing the hopes of millions of fans that it would be out in time for Christmas.

Nigel Newton, chief executive of Ms Rowling's publisher Bloomsbury, said today that the author of the best-selling books was still "happily writing number five" of the seven-volume series.

Mr Newton delivered the blow at today's release of the publishing house's profit figures, adding that the publication date of the latest book - Harry Potter and the Order of the Phoenix - would not be announced until it had been delivered by the author.

One publishing source said: "If she is still writing it is extremely unlikely that it will be out by Christmas, as the scripts will need to be proof read and edited before they are printed and distributed. I wouldn't expect the book to be on the shelves until next year."

Rosamund de la Hey, Bloomsbury's children's books marketing director, said Ms Rowling had written one book a year between the first, Harry Potter and the Philosopher's Stone, which was published in 1997, and the fourth, Harry Potter and the Goblet of Fire, which came out in July 2000. Ms de la Hey said the author was keen to spend more time on the latest.

She said: "The reason that JK Rowling is still writing is simply that the last one she did in a huge rush. She is doing this one to her complete satisfaction."