From Princess Diana's threatening phone call to destroying Charles' painting, 7 shocking revelations in Camilla's biography

After Princess Diana's secret tapes made some shocking revelations about her life after marriage and Prince Charles' affair with Camilla, now Duchess of Cornwall's biography has made some explosive claims about the late Princess of Wales.

The biography – The Duchess: The Untold Story – by royal author Penny Junor paints a different picture of Diana and Charles-Camilla's affair. The biography, which is pegged to Camilla's 70th birthday, also talks about Queen Elizabeth's relationship with Charles and Camilla.

Here are 7 shocking revelations from Camilla's biography

Princess Diana's threatening phone call to Camilla

The biography claims that paranoid Diana would call Camilla to tell her that she has sent someone to kill her.

"Without saying who was calling, she'd typically say: 'I've sent someone to kill you. They're outside in the garden. Look out of the window; can you see them?'", Junor claimed in the biography.

Diana destroyed Charles' painting

It was during their honeymoon when Diana saw Charles painting on the veranda deck of Britannia and she destroyed it. "When Charles was painting on the veranda deck of Britannia, he went off to look at something for half an hour. He came back to find [Diana had] destroyed his painting and all his materials," the author mentioned.

Camilla's letter broke Prince Charles' heart

Before Camilla tied the knot with Andrew Parker Bowles, she wrote a letter to Charles informing him about her marriage. Her letter broke Charles' heart.

"She wrote to Charles herself to tell him. Her letter broke the prince's, heart. In great distress, he fired off anguished letters of his own to his nearest and dearest," according to the excerpt from the biography.

"It seemed to him particularly cruel, he wrote in one letter, that after 'such a blissful, peaceful and mutually happy relationship', fate had decreed that it should last a mere six months."

When Charles threw Diana's wedding ring

After their marriage, Charles right-hand man Michael Colbornes sat with Diana for six hours when she cried, kicked the furniture and ranted about everything. Later that evening, Charles opened the door and came out shouting, "Michael!" Charles threw something at him and when he caught that he realised it was Diana's wedding ring.

Diana had lost weight and the ring no longer fitted her. She wanted Charles to make it smaller.

Queen Elizabeth left Camilla to comfort Charles after Diana's death

The day when the Royals were informed about Diana's death, Charles and Queen Elizabeth II were together, but she left the comforting to Camilla.

Camilla was not invited for Charles' 50^th birthday celebrations

Charles children – Prince William and Prince Harry – threw an advance surprise party in November 1998 to celebrate their father's half century and they invited Camilla. However, when Queen gave an official birthday party for Charles' 50^th birthday, she invited 1,000 guests, but that did not include Camilla.

Camilla's party that made Diana's blood boil

Charles threw a party for Camilla and that made Diana furious. But it wasn't only the party that made her furious. Generally, Camilla would enter the house secretly, but on that particular day she arrived at the gate and let photographers get good photos of her.

"She was the first to arrive, sweeping into Highgrove last night with all the confidence of a queen," Junor explained.