Prince William
Prince William pays a heartfelt tribute to his grandmother the QueenGetty

Prince William has paid a heartfelt tribute to his grandmother the Queen. In an introduction to a biography of the Queen by Lord Hurd to commemorate her longest-serving reign, the Duke of Cambridge praised the Queen for providing 'continuity' and 'reassurance' for the nation through the 'uncertainty' of the 'rapid social change' of recent times.

The Prince says that the country has changed 'almost beyond recognition' during the Queen's reign, but praises Her Majesty for embracing the future without compromising her own traditional values of 'family and charity'.

Describing her influence on him personally, the future heir to the throne said he draws strength from her example, adding that he feels 'privileged' to have her as a role model. "Over the last 90 years, the world has changed more rapidly than at any time in history," he said. "When my grandmother the Queen was born in 1926, the wounds of the Great War were still healing, but few would imagine how soon they would be reopened.

"The confidence of the previous century had morphed into uncertainty and many worried – as they still do – about the challenge presented to our communities by rapid technological and social change.'

"I think I speak for my generation when I say that the example and continuity provided by the Queen is not only rare among leaders but a great source of pride and reassurance. Time and again, quietly and modestly, the Queen has shown us all that we can confidently embrace the future without compromising the things that are important."

The Prince also acknowledges the close personal bond the Queen shares with the younger royals in her private role as a grandmother and great-grandmother.

He says: "The Queen's kindness and sense of humour, her innate sense of calm and perspective and her love of family and home are all attributes I experience first-hand. I should add that no mention of the Queen is complete without paying tribute to my grandfather Prince Philip, who has devoted his life to supporting her.

"All of us who will inherit the legacy of my grandmother's reign and generation need to do all we can to celebrate and learn from her story. Speaking for myself, I am privileged to have the Queen as a model for a life of service to the public."

The Prince's very personal tribute was welcomed by Royal commentators. Biographer Penny Junor said: 'I think these are very touching words. He talks about her as not just a leader but a role model for a life of service to the public. The attributes he lists and finds admirable are the very attributes we would want our future king to subscribe to.'

Royal biographer Hugo Vickers added: "I am very pleased that he uses her as a role model because I don't think he could have a better one. I think Prince William and the younger Royals learn by example which is one of the great advantages of an hereditary monarchy.

"He will do things the way he wants to do them in the fullness of time of course, but he will no doubt bear in mind how she does things."

Prince George at Princess Charlotte's christening
The Queen with Prince William, Kate and Prince George at the christening of Princess CharlotteWPA Pool/Getty

On Wednesday 26 August, at around 5.30 pm the Queen will have been on the throne for 63 years, seven months and two days, equalling the record held by her great-great grandmother, Queen Victoria.

The Queen however, has no intention of celebrating the momentous milestone on the actual day out of respect to Victoria and is determined there be 'no fuss'. A senior aide said: "We are not aware of any private plans [to celebrate on September 9], the Queen made it clear she wanted no fuss." A source added: "She would see that as very disrespectful to one of her ancestors."

Instead, for the 89-year-old royal it will be business as usual as she opens a new railway line in Scotland. The occasion will be marked next June, when the Queen celebrates her 90th birthday.