Princess Diana's brother tells the "truth" in his new book

Earl Spencer will publish a new book telling the life story of his sister, Diana, Princess of Wales, from his perspective.

The book "Swan Song: Diana, My Sister" is scheduled to be published in the United Kingdom next month, nearly 30 years after her death.

Speaking about his motivations for writing the book, Earl Spencer said: “I want to speak on behalf of Diana, and do so in a positive and frank way.”

He added that he hopes the book will help people understand Diana's character as she really was, describing her as "a unique and vibrant person, full of love, charisma, and self-doubt. She went through life with everything she had, and left the world a much better place, despite her passing while she was still very young."

Princess Diana died at the age of 36, following a car accident in Paris in 1997, and she was supposed to turn 65 at the beginning of July of this year.

Her sons, Prince William and Prince Harry, were 15 and 12 years old, respectively, at the time of her death.

In a statement issued on Tuesday on the occasion of the announcement of the new book, Earl Spencer said that he had received "an influx of requests again" to conduct interviews covering his sister's life, as the thirtieth anniversary of her death approached.

He said: "This convinced me to write down my thoughts and memories myself, once and for all, instead of finding myself again faced with the opinions of others, many of which are based on incorrect information that has become established over time as if it were facts."

He added: "The aim of this book is to tell the truth about Diana from her brother's point of view, just as I tried to do when I spoke at her funeral," referring to the eulogy he delivered at Westminster Abbey in September 1997.

Spencer said he hoped the book would be of interest to those who "still cherish" Diana's memory and remember her during her lifetime.

He continued: "I would be very happy if those who were too young to remember her at the height of her presence, after reading the book, feel that they now understand who she really was."

In his eulogy at her funeral, Earl Spencer described Princess Diana as “the essence of compassion, duty, elegance and beauty,” adding: “Around the world she was a symbol of selfless humanity... and a standard-bearer for the rights of those who were subjected to the greatest forms of injustice.”

He also criticized the media in his speech, described Diana as “the most persecuted person in the modern era,” and pledged to protect Princes William and Harry from meeting a similar fate.

The book is scheduled to be published in the United Kingdom on September 22, by Penguin Michael Joseph, a subsidiary of the Penguin Random House group.

Daniel Bonyard, publishing director at Penguin Random House in the United Kingdom, said: “Although these pages contain much new information that will attract great interest, readers will find in them, for the first time, a fitting tribute to the beloved woman that Princess Diana was, and this tribute will remain a testament to her.”