The Duke of Sussex’s popularity has sunk to a record low following a number of claims about the royal family in his upcoming book, according to a new poll.

Almost two-thirds (64%) of Britons have a negative view of Harry, up from 58% in May, with just a quarter (26%) seeing him in a positive light, according to the YouGov survey.

The results come ahead of the release of Harry’s book Spare, due out on Tuesday, which has sparked a furore, following claims the Prince of Wales physically attacked him.

Harry’s net favourability among the British public is at an all-time low of minus 38, with his wife, the Duchess of Sussex, recording minus 42.

The King’s youngest son’s net favourability score among 2019 Labour voters is minus seven, while among 18-24-year-olds, the proportion of positive and negative views of him was equal (41%).

Meghan still has a positive net favourability score of 10 among 18-24-year-olds, but this has dropped from 55 in 2017.

She holds a score of minus 11 among 2019 Labour voters and minus 30 among Remain voters, with minus 81 and minus 72 among 2016 Conservative voters and Leave voters, respectively.

Harry’s tell-all-tales in the book include how he killed 25 Taliban members during the Afghanistan war, recounting how he took cocaine and magic mushrooms, and losing his virginity to an older woman in a field behind a pub.

In television interviews, the duke has said he is “not texting” his brother, described the Queen Consort as “the villain” and criticised “family members” for a “really horrible reaction” when the Queen died.

He spoke to ITV presenter Tom Bradby, denying branding the royals racist and accusing his family of “getting into bed with the devil”.

Harry’s net favourability among the British public is at an all-time low of minus 38, with his wife, the Duchess of Sussex, recording minus 42.

The King’s youngest son’s net favourability score among 2019 Labour voters is minus seven, while among 18-24-year-olds, the proportion of positive and negative views of him was equal (41%).

Meghan still has a positive net favourability score of 10 among 18-24-year-olds, but this has dropped from 55 in 2017.

She holds a score of minus 11 among 2019 Labour voters and minus 30 among Remain voters, with minus 81 and minus 72 among 2016 Conservative voters and Leave voters, respectively.

Harry’s tell-all-tales in the book include how he killed 25 Taliban members during the Afghanistan war, recounting how he took cocaine and magic mushrooms, and losing his virginity to an older woman in a field behind a pub.

In television interviews, the duke has said he is “not texting” his brother, described the Queen Consort as “the villain” and criticised “family members” for a “really horrible reaction” when the Queen died.

YouGov surveyed 1,693 adults in the UK at the end of last week.