Trump a 'lying narcissist shaped by his bullying father', niece says, as White House cries foul

US President Donald Trump's niece paints him as a lying narcissist who was shaped by his domineering father in her memoir.

The memoir is due out on July 14 amid a legal battle to stop its publication and is already a best-seller on Amazon.

The 240-page book says Trump is a product of his "sociopath" father Fred Trump who created an abusive and traumatic home life, The Washington Post reported.

The memoir is billed as the first unflattering portrayal of Trump by a family insider.

She writes that her uncle meets all the clinical criteria for being a narcissist, according to The New York Times.

Mary, a clinical psychologist, also writes that Trump saw "cheating as a way of life," according to The New York Times. She alleges that the future US leader paid someone else to take the SAT pre-collegiate exam, helping him get into the University of Pennsylvania's prestigious Wharton business school.

Also read | Trump paid proxy to take college entrance exam for him, claims niece's new book

Mary is the daughter of Fred Trump Jr, Trump's older brother, who died in 1981 from complications related to alcoholism.

The president's younger brother Robert Trump tried to block publication, arguing that Mary was violating a non-disclosure agreement signed in 2001 after the settlement of her grandfather's estate.

The book is set to be the latest bombshell book to dish dirt on Trump after former aide John Bolton's tome, which describes the Republican leader as corrupt and incompetent, hit shelves last month.

The White House immediately hit back, describing Mary Trump's "Too Much and Never Enough: How My Family Created the World's Most Dangerous Man" as "a book of falsehoods."

"(The president) said his father was loving and not at all hard on him as a child," deputy White House press secretary Sarah Matthews said in response.

"Mary Trump and her book's publisher may claim to be acting in the public interest, but this book is clearly in the author's own financial self-interest," she added.

Trump has also described that book as "fiction."