Dickie Arbiter, the Queen’s former press secretary, said: “It’s important to understand that for the Queen this marks the anniversary of the day her father died.

“She has always made it clear that her long reign is a consequence of her father’s early death and so it is not a day for celebration.

“She will go to church the day before and her father will be in her thoughts then. On the day itself, she will do her red boxes but she won’t be going out and about anywhere.”

Sandringham is filled with memories of George VI - it was in a bedroom there that he died in his sleep after suffering from lung cancer and, at the church of St Mary Magdalene, his coffin rested for two days before he was taken to London for his lying in state.