Amazon has advised readers to buy from other retailers after breaking its silence over a high-profile dispute with the publisher Hachette, which has drawn in the British authors Ian Rankin and JK Rowling.
In a post on the Kindle website, Amazon told customers: "If you do need one of the affected titles quickly, we regret the inconvenience and encourage you to purchase a new or used version from one of our third-party sellers or from one of our competitors."
In a blog post, the world's largest distributor of books has told customers it does not expect resolution soon. In a dispute affecting Amazon's US website, the company has acknowledged for the first time that it is no longer taking pre-orders for Hachette titles and that deliveries will take longer than usual.
On Friday, Amazon provoked a wave of protest from authors and publishers after its American website stopped taking advance sales of JK Rowling's forthcoming detective novel The Silkworm, which will appear on 19 June under her alias Robert Galbraith.
Pre-orders play a big part in boosting new releases into the best seller lists, which in turn help fuel more sales.
Amazon has also reduced Hachette stock in its warehouses, so that new orders have to be sent to its warehouses by the publisher before being posted on to customers, delaying the time it takes for physical books to reach the reader.
Hachette confirmed that Amazon had also removed its usual discounts from the publisher's books in the US, meaning Ian Rankin's latest inspector Rebus mystery costs twice as much on Amazon.com than on Amazon.co.uk.
"Unfortunately, despite much work from both sides, we have been unable to reach mutually acceptable agreement on terms," Amazon said. "Hachette has operated in good faith and we admire the company and its executives. Nevertheless, the two companies have so far failed to find a solution. Even more unfortunate, though we remain hopeful and are working hard to come to a resolution as soon as possible, we are not optimistic that this will be resolved soon."
The levers Amazon is pulling with Hachette are similar to those used in its last big public showdown with a publisher. Pre-orders were removed from Macmillan titles when the two companies fell out in 2010.
The negotiations with Hachette are understood to centre on the extent to which the French owned publisher shares ebook profits, which can be sizeable. These cost little to produce and distribute compared with physical books, because there are no expenses for paper, printing, distribution, warehousing and returns.
It is unusual for Amazon to comment in response to media reports, but the company has come under fire across Europe over tax, the treatment of its workforce in Germany, and is now under pressure from shareholders.
After years of gains, Amazon's share price has begun to fall, and is down 20% so far this year. The company does not pay a dividend, preferring to reinvest profits, but some investors now want founder Jeff Bezos to begin sharing more cash.
In a move designed to placate authors, the company said it had offered to help top up royalties for any writers affected by the dispute.
"We've offered to Hachette to fund 50% of an author pool – to be allocated by Hachette – to mitigate the impact of this dispute on author royalties, if Hachette funds the other 50%. We did this with the publisher Macmillan some years ago. We hope Hachette takes us up on it."
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