The book is known only as 4C Untitled Flatiron Nonfiction Summer 2023 and as yet has no author attached to it.

But Swifties - fans of the star - have pieced together their own clues that she is the writer and have been pre-ordering it in their droves.

The book, which will be published by Flat Iron, an imprint of Macmillan, rose as high as number two in Amazon's book sales chart and topped Barnes and Noble's pre-order chart.

The publisher has not responded to a request from Sky News to confirm or deny the rumours of the book's authorship.

So what are the clues that had Taylor Swift fans willing to shell out $45 (£35) on a 544-page hardback they know nothing about?

First off the number of pages has something to do with it. 5 + 4 + 4 = 13 - and as any good Swiftie knows, 13 is the star's lucky number.

Eagle-eyed fans also identified what they took to be hints in the singer's social media posts announcing the release of her upcoming re-released album, Speak Now (Taylor's Version).

"My version of Speak Now will be out July 7 (just in time for July 9th, iykyk)", she wrote.

Swift, 33, who is currently touring stadiums in the United States, also addressed the post to "Dear reader" - an innocuous reference to a track off her latest album, Midnights (3am Edition), or a nod to an upcoming book?

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A screenshot from the publisher was posted online with more information about the launch, indicating a huge print run of one million copies.

"It is fun and NOT political!" the publisher's note said, along with instructions that booksellers would have to sign an affidavit to get copies ahead of the launch.

The title and author will be revealed officially on 13 June.

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According to a report by Variety, however, Swift fans who have pre-ordered the tome will be disappointed.

The magazine has authoritatively said the memoir is not hers - although it doesn't reveal who the author could be.

Some have their money on K-pop group BTS. The publication date is also "Army day", when fans of the boy band celebrate the group and their fandom.