Queen Elizabeth II was 'lukewarm' to the idea of princesses one day taking the throne, a bombshell new book has claimed.
The late monarch was reportedly not overly enthusiastic about potential changes to Britain's ancient primogeniture law.
The custom oversees how an estate can be divided, with the firstborn child traditionally inheriting it. In royal lines, it would see the eldest son ascending to the throne, ahead of an older sister.
But before her death, the late Queen oversaw a change to the law of succession in 2013 replacing the historic male-preference with absolute primogeniture, allowing the eldest child of the sovereign to inherit, regardless of gender.
However, according to a new book, the beloved monarch and her aides at Buckingham Palace were seemingly less than keen on the overhaul, which was delivered as part of former Prime Minister David Cameron's constitution reforms.
The now Lord Cameron spoke to Julia Gillard, the then Australian PM, about his aim to unveil the new primogeniture law during a Commonwealth summit in Perth in October 2011, six months after the current Prince and Princess of Wales were married.
However, in his book Power and the Palace, author Valentine Low wrote: 'According to a government source, he said to Gillard: "William and Kate are getting married, there's going to be kids, shall we sort this out?".
'Crucially, the palace was not against it. But they said that the government had to ensure the backing of the other 15 realms.'
The late Queen Elizabeth II with her family at Buckingham Palace. The sovereign oversaw a change to the law of succession that ensured the firstborn child of a monarch would be next in line to the throne regardless of gender
Plans to change the law of succession were discussed six months after the current Prince and Princess of Wales were married (pictured are Prince William and Catherine with son George)
The late Queen is picture with Catherine, who was then the Duchess of Cambridge in 2012
The source is quoted as saying: 'I always thought that the signals from Buckingham Palace were that if it was the wish of the duly elected prime minister of the day, and the realms can be sorted out, we will not stand in its way. I didn't get the sense there was any great enthusiasm from the palace and the Queen herself.'
According to Mr Low's book, Buckingham Palace 'firmly' instructed Whitehall to deal with it on the proposed law reforms, and reportedly demanded the government not to approach any of the aides working for the then Prince Charles or his son, William.
Future monarch Charles, who was the Prince of Wales at the time, was said to be keenly interested in the government discussions over the Succession to the Crown Act.
The future King is said to have later 'ambushed' Richard Heaton, permanent secretary to the Cabinet Office, with questions about the legal reform.
News of the apparent encounter was then broken by the Daily Mail, with a source telling this paper at the time Charles was concerned of the 'unintended consequences' of the 'rushed' rule change.
The King is said to have backed the principle of changing the law so that if the child is a girl she would become Queen. However, he was reportedly frustrated that neither he nor Prince William had been consulted about the royal inheritance overhaul.
According to former The Times royal correspondent Mr Low's book, Jeremy Heywood - who was cabinet secretary at the time - later told Mr Heaton Charles was 'in the dog house' over the revelations.
Elsewhere, the book claimed the late Queen had also voiced her concerns about 2016's historic Brexit vote to leave the European Union.
Queen Elizabeth II reportedly voiced her concerns about Brexit ahead of the historic 2016 vote which led to Britain leaving the European Union
The book also claimed the late Queen left a state banquet to comfort a teenage Prince Charles as he prepared to receive his O-level results (a young Charles is pictured as a teen in 1965 with his mother)
King Charles is pictured with his wife Queen Camilla after his coronation in May 2023
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The monarch appeared to weigh in on the debate about the future of her realm, with the Queen reportedly telling a senior minister just three months before the crunch vote: 'We shouldn't leave the EU.'
She had apparently added: 'It's better to stick with the devil you know.'
In other revelations, Mr Low's book also details how the Monarch comforted a teenage Charles on the eve of his O-level results.
In a display of motherly affection, the Queen reportedly left a state banquet early to be by her anxious son's side as he braced himself to collect his exam marks.
Recounting the story, Mr Low describes how Labour MP Barbara Castle was talking to the monarch about Africa at the banquet before the Queen departed.
'Their conversation came to a premature end when a flunkey came and whispered in the Queen's ear and she excused herself, "saying laughingly that 'poor Charles' was doing his O-levels the next day and just wanted a bit of reassurance"," the book says.
'When she came back, Castle was talking to Princess Margaret, and the Queen said to her sister: "You and I would never have got into university".
'In the state room afterwards Castle's husband told her: "You've been monopolising the Queen." To her surprise, she had "enjoyed myself far more than I thought I would".'
Power And The Palace: The Inside Story Of The Monarchy And 10 Downing Street by Mr Low will be published on September 11.