The Duchess of Cornwall made a "mafia thug move" towards Princess Diana after learning of her engagement to the Prince of Wales, a prominent royal journalist has claimed.
In footage from CNN's new series "Diana", writer and broadcaster Bidisha Mamata details an “unbelievable” action taken by Camilla when she found out about the royal couple's plans.
She says: “Camilla Parker Bowles left Diana a note saying 'Such exciting news. Love to see the engagement ring'."
Ms Mamata said that appeared to be a "power move", and likened it to the tactics of lead character Regina George from the 2004 film Mean Girls.
She told CNN: "That's like a real mafia thug move. That's so Mean Girls it's unbelievable.
"That's a power move right there."
Former BBC royal correspondent Jennie Bond said that the devilish note revealed fractures that existed in Charles and Diana's marriage from the beginning.
Ms Bond said: “In Diana’s own words, she told me any marriage Prince Charles might have made could never be as strong as the relationship he had with Camilla.
“And that’s what she was battling with from the outset.”
The Prince of Wales and Diana were dating for about six months before he proposed in the nursery at Windsor Castle on 3 February 1981.
They officially announced their nuptials during an exclusive interview on 24 February 1981.
But Charles's storied connection to Camilla dated back 10 years before that, after they first met at a polo match at Windsor Great Park in 1970.
They dated for six months after this first encounter, but had to break things off when Charles left to serve in the Royal Navy - spending an extended period of time away from the UK.
By the time he returned, she had become engaged to Andrew Parker Bowles.
They later reignited their love affair in 1986 while Charles was still married to Diana.
In an audio tape made with biographer Andrew Morton, Diana recalled storming over to the adulterous pair at party in 1989 where she said: "I know what's going on between you and Charles, and I just want you to know that."
The popular royal couple would divorce in 1992, five years before Diana tragically died in a car crash in Paris.
Prince Charles and Camilla Parker Bowles finally tied the knot in a civil ceremony at Windsor Guildhall on 9 April 2005.
