A high street retailer has moved its launch for the new Harry Potter book from King's Cross following last week's bombings.
The sixth book goes on sale at midnight on Friday night
Harry Potter and the Half-Blood Prince, the sixth book from author JK Rowling, is released worldwide on Friday night.
WH Smith originally planned to launch the book at King's Cross station, where boy wizard Harry Potter traditionally catches the train to Hogwarts School.
The launch will now be held at a store in Wimbledon, south-west London.
In the US, where stocks of more than 10 million Harry Potter books are poised to go on sale on just after midnight on Friday night, an online bookseller has announced plans to meet demand by buying used copies for $5 (£2.80).
Alibris, which buys and sells old library books and leftover bookshop stock, will pay $5 plus postage costs for good condition copies of Harry Potter and the Half-Blood Prince.
There is a strict embargo on sales of Potter books
Marty Manley, of Alibris, said the company was targetting parents who may have to buy more than one copy of the book according to the number of children in the family.
"I have two boys, a 9-year-old and a 13-year-old, and I'm sure I'm going to be buying two books so I'm going to end up with one extra," said Mr Manley.
"With this book it wouldn't take a very large share of the primary market to get the secondary market going," he added.