Sep 18, 2009, 11:01 GMT
Paul Burrell is set to reveal "the truth" of Britain's Princess Diana's relationship with the Queen Mother.
Friends say the former royal butler - who worked for the Princess of Wales for 10 years before her death in 1997 - is likely to "spill the beans" about the women's friendship after the issue was left out of a new book about the royal matriarch.
Diana and Elizabeth - who died in 2002, aged 101 - were known to have been close, but Diana was barely mentioned in William Shawcross' official biography 'Queen Elizabeth: The Queen Mother'.
An insider said: "To be fair, if anyone knows what really went on between Diana and the Queen Mother, it's Paul.
"The Shawcross book may just force him finally to tell it how it was, as he can't stand the idea of Diana being ignored in such a way."
Another added: "It's only a matter of time before he speaks out. Paul is a lot more nervous than he used to be about speaking out but this is an important piece of royal history he can shed some light on."
Paul was accused of profiting from the death of Diana after he gave a series of interviews and wrote a tell-all book about his time working for the royal.
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