The statement from King Charles was swift, and stark. The authorities have “our full and wholehearted support and co-operation,” it read, and “the law must take its course.”

Hours earlier, his brother had been arrested at his home on a private estate the monarch owns – Sandringham, north of London. Even by the standards of a family not unused to controversy, it was a stunning development.

Brief at little more than 100 words, the King’s response – in his own name – could not have been clearer. “My family and I will continue in our duty and service to you all,” it concluded. Translation: I will put my duty to the country before any residual sympathy I may have with my younger brother.

It’s understood that Prince William and Catherine, Princess of Wales backed the statement – the most senior royals united in the strategy.

The King’s tactics in dealing with the unfolding allegations around Andrew have stood in contrast to that of his late mother, Queen Elizabeth II.

Andrew was, reportedly, her favorite son, and critics have previously said she did not act quickly enough to hold Mountbatten-Windsor to account for the repercussions of his friendship with convicted sex offender Jeffrey Epstein.

Many have questioned why she allowed him to use Buckingham Palace as the location of his disastrous 2019 BBC interview in which he tried to bat away allegations of wrongdoing.