WASHINGTON - Nearly half of Americans believe the Duke and Duchess of Sussex should both be stripped of their royal titles, according to a new poll.

Harry and Meghan have enjoyed greater popularity in the US than the UK in recent years, with a poll taken last month showing just 27% thinking they should lose their titles.

But after the couple's Netflix documentary and the publication of Harry's autobiography, Spare - which saw the prince repeatedly interviewed US television - Americans appear to have significantly fallen out love with the royal couple. For the time being at least.

The Redfield and Wilton poll for Newsweek found 45% are now in favour of Harry and Meghan losing their royal titles – an increase of 18% from last month.

The poll also found that 26% think the couple should keep their title – a big drop from the 43% of those who answered that way in December.

Harry himself hinted that the couple would not give up their titles when asked by Anderson Cooper on his 60 Minutes interview.

Asked about it, Harry said: "What difference would that make?"

The couple's UK popularity has also tumbled recently. After the release of their Netflix documentary last month, a YouGov poll for The Times found that 44% of Brits thought Harry and Meghan should have their titles removed, compared to 32% who said they should not.

Meanwhile, recent polling on the couple's popularity in the UK has seen them plumb new depths, with just 24% now thinking positively of Harry, compared to 68% who have a negative opinion.

This gives him the lowest ever rating on YouGov's royal favourability tracker, having dropped to -44 from -38 last week, which was a previous record low.

Among over-65s, Harry and Meghan are more disliked that Prince Andrew, while Meghan's popularity is even lower than Harry's, with just 8% of the public saying they have a positive view of her.

Harry's memoir, which hit the shelves on 10 January, includes claims that the Prince of Wales physically attacked him and teased him about his panic attacks, and that the King put his own interests above Harry’s and was jealous of the Duchess of Sussex and the Princess of Wales.

In a US broadcast promoting the work, Harry branded the Queen Consort the “villain” and “dangerous”, accusing her of rehabilitating her image at the expense of his.

He also described his late mother, Diana, Princess of Wales, as his “guardian angel” and said she is with him “all the time”.

Buckingham Palace and Kensington Palace have not commented on the contents of Spare or the Netflix series.