Camilla, the Duchess of Cornwall, reportedly made a "mafia thug move" towards Princess Diana after she learned of the latter's engagement to Prince Charles.

Charles and Camilla were on-and-off lovers for several years before they finally tied the knot in 2005. Camilla had been married to Andrew Parker-Bowles for eight years and shared two children with him when the Prince of Wales announced his engagement to Diana in 1981, but there was still a lot of drama between them.

Royal journalist Bidisha Mamata claimed in CNN's new series "Diana" that Camilla made a "power move" when she came to know about Charles and Diana's engagement plans. She said, "Camilla Parker Bowles left Diana a note saying 'Such exciting news. Love to see the engagement ring'."

Mamata likened Camilla's letter to the tactics of lead character Regina George from the 2004 teen drama "Mean Girls." She said, "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 also spoke of the controversial letter, noting that it revealed fractures that existed in Charles and Diana's marriage from the beginning. She explained, "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 heir apparent announced his engagement to Diana Spencer in February 1981, weeks after he proposed to her in the nursery at Windsor Castle. They had only been dating for six months at that time, whereas Charles and Camilla had known each other for a decade.

The future monarch couple first met at a polo match at Windsor Great Park in 1970, and dated for six months until Charles had to leave to serve in the Royal Navy away from the UK. By the time he returned, she had become engaged to Andrew Parker Bowles.

Charles and Camilla reignited their love affair in 1986 while Charles was still married to Diana. The Princess of Wales famously admitted the affair in her 1995 Panorama interview, saying, "Well, there were three of us in this marriage, so it was a bit crowded."

Charles and Camilla tied the knot in a civil ceremony at Windsor Guildhall on April 9, 2005, over seven years after Diana lost her life in a car accident in Paris.

Diana & Camilla At Ludlow Races
Diana Spencer and Camilla Parker-Bowles at Ludlow Races where Prince Charles is competing, 1980. Express Newspapers/Archive Photos