Copies of a new memoir promising fresh revelations about the life of Princess Diana have reportedly been stolen from a delivery truck ahead of its release.

Written by the late princess’s brother, Charles Spencer, the book is scheduled for global release later this month – almost 30 years after Diana’s death in August 1997 following a car crash in Paris.

Spencer has said he was inspired to write Swan Song: Diana, My Sister after being inundated with fresh interview requests in the lead-up to the anniversary.

“This has ⁠convinced me to write down my own thoughts and memories, once and for all, rather than having the discomfort of again reading the opinions of others, many of which are based on untruths that have become accepted over time.”

Now, on the eve of its release, several copies of the highly anticipated book have been stolen from back of a delivery truck when it was parked at a lay-by in the Netherlands while en route to a warehouse, according to the UK Daily Mail.

The newspaper, which has a deal to publish a serialisation of Swan Song before it becomes available in stores, describes it as a “bombshell” memoir.

It reported that just four books – “wrapped in black plastic to hide their contents” – had been taken, although the truck was carrying thousands of copies.

“It’s extremely suspicious,” a publishing source was quoted as saying.

“Nothing like this has ever happened before. This is probably the biggest book of the year and the security surrounding it has been incredibly tight.

“Every possible precaution has been taken to prevent it from being leaked ahead of its serialisation.”

 

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Swan Song is published by Michael Joseph, a division of Penguin Random House, whose director has previously described it as a “book of historic importance”.

It is expected to include revelations about Diana’s unhappy marriage with the Prince of Wales – now King Charles – whom she wed in a glittering ceremony in 1981 but divorced in 1996 after their relationship turned sour.

The princess – mother of heir-to-the-throne Prince William and his brother Prince Harry  – was just 36 when she died. She was fatally injured when a car carrying her and her lover Dodi al-Fayed crashed in the Pont de L’Alma tunnel in Paris as it sped away from  paparazzi photographers on motorbikes.

Charles Spencer (centre) walked between Diana’s two sons at her funeral. Photo: Getty

Spencer’s memoir will also share his perspective on the royal family’s response to the crash, which at the time provoked a strong backlash from the public.

At her funeral, her brother famously delivered a eulogy in which he castigated the royals.

“The aim of this book is to tell the truth about Diana from her brother’s perspective, just as I attempted to do when speaking at her funeral,” Spencer has said.

On the weekend, he shared a photograph of himself on social media holding a copy of the memoir, describing it as the most personal of the 10 books he has written over the past decade.

“At heart, this is a brother’s simple tribute to an extraordinary sister,” Spencer wrote.

“A month ago I read ‘Swan Song’ out, over three days, for a recording so that it could be available on audiobook.

“When I finished the recording, I thought: ‘That is exactly what I wanted and needed to say – and she would, I reckon, have approved of every word’.”

It was revealed last week that Diana’s “revenge dress” – which she wore on the same night her then-husband the Prince of Wales publicly admitted his infidelity on national television – is going back on public display ahead of its auction next month.