The logo for J.K. Rowling's new project. Pottermore Facebook page

Harry Potter author JK Rowling has launched a website to promote a secretive new project.

The site, pottermore.com, features a holding page with two owls which links to a YouTube page featuring a countdown to a 23 June announcement.

"The owls are gathering... find out why soon," it adds.

Her spokeswoman said the project was "not a new book" and was not "directly related" to the final Potter film which is due out on 15 July.

"We are not saying anything more at the moment," she added.

"Pottermore" was trademarked in 2009 by Warner Bros, which distributes the Potter films. The trademark description of Pottermore suggests an interactive site "providing online chat rooms and electronic bulletin boards".

Pottermore.com also has a Twitter account, twitter.com/pottermore.

News of Pottermore.com emerged on Wednesday with messages sent to nine Potter fan sites and an official Potter Twitter account. Each site received one letter, the letters spelling out "pottermore".

Producers of fan site The Leaky Cauldron said they had seen a preview of the Pottermore project, describing it as "breath-taking" before adding : "That is all we are permitted to say at the moment."