Prince William and Kate’s popularity plunges after Prince Harry’s memoir Spare

Prince of Wales's popularity plunges after the publication of Prince Harry's memoir, Spare.  Since the book was published on January 10, the Prince of Wales's ratings have plunged eight percentage points, while his brother's have dipped seven points, according to Ipsos Mori. The Princess of Wales has dropped seven points and the Duchess of Sussex, five points.

Prince Harry took particular aim at Prince William in his book, describing decades of simmering resentment and rivalry. He accused his brother pushing him to the floor and causing physical injuries during a row at his Kensington Palace home and of lunging at him after the Duke of Edinburgh's funeral.

However, the book has had little impact on the reputation of the royals overall, with 53 per cent saying they feel favourable towards the Royal Family and 51 per cent to the King. The Prince and Princess of Wales remain the most popular royals, with ratings of 61 per cent and 60 per cent respectively.

Almost 70 per cent think William will be a good king. By comparison, Prince Harry's favourability now stands at 23 per cent, compared to almost 70 per cent in 2018. His unfavorability is at 53 percent, compared to around 10 per cent in 2018.

In the US, now home to the Sussexes, the Princess is the most popular royal on 47 per cent, with Harry on 4- per cent, William on 40 per cent and Meghan on 35 per cent.

There too, both Harry (-11) and William (-13) have been hit by the book's publication.  Kelly Beaver chief executive of Ipsos in the UK and Ireland, said: "Both Prince Harry and his brother Prince William seem to have suffered in British public opinion following the release of the Duke of Sussex's memoir and the claims within it - and there is some evidence other members of the Royal Family are feeling the fall-out too.   "This data also re-emphasises the need for the monarchy to show it can speak to and be relevant for younger generations."

She added: "The comparison with the US is interesting - as we might expect, Americans are less likely to have strong views about the monarchy than Britons and are less convinced about its benefits.  But they do feel more positive towards Prince Harry and Meghan than the British - although the Prince and Princess of Wales get relatively favourable views there too.

"But the immediate impact on public opinion should not be exaggerated - and it should be noted is partly a return from the uplift in public sympathy after the sad passing of the Queen.

"Britons are still much more positive than negative towards the King, the Prince and Princess of Wales and the Princess Royal, and towards the Royal Family as a whole, and views towards the institution as a whole are so far little changed. While the stories may have challenged the public's views towards the individuals involved, the monarchy itself endures for now." Ipsos interviewed 1,000 adults aged between 18 and 75 in the UK on January 10 and 11.

The US results are from an Ipsos poll of 916 adults conducted between January 11 and 12.