Prince Charles' former press secretary insists the royal was "besotted" with Princess Diana and often "squeezed her bottom".
Dickie Arbiter has defended his former employer after his popularity was claimed to have slumped somewhat following findings in a recent poll, insisting he "absolutely adored" the late Princess of Wales - who died in a Paris car crash in August 1997 - and used to be "all over" her.
He wrote: "For years now, Prince Charles has been presented as the bad boy of the Royal Family: having an affair, portrayed as never really having loved Diana and singled out to blame for the disintegration of their marriage. Yet in my experience, they absolutely adored each other, and embarked on married life in 1981 with the highest of intentions.
"Three days before they married, I had tea with Charles and Diana at Buckingham Palace. Back then, I was a radio reporter for Independent Radio News and a presenter for LBC, and they were all over each other like a rash, holding hands, giggling and clearly utterly besotted.
"Equally, once returned from honeymoon and together during public engagements, Charles was tactile and would think nothing of squeezing her bottom, something I noticed more than once. You can't fake that sort of affection."
Dickie also insisted Charles will be a "modern king" in response to a YouGov poll which found just over a quarter of people (27 per cent) think the Prince of Wales has had a negative impact on the monarchy, up 12 per cent from 2013.
It also discovered 36 per cent of people think he has been positive for the Royal Family compared to 60 per cent four years ago.
Writing in the Daily Telegraph newspaper, he added: "To chastise the Prince unendingly for his relationship with Camilla is deeply unfair. If anything, he will be a modern King, with a deeper trove of life experience, because of it.
"Equally, when judging the heir to the British throne, one might be better of considering his conduct in the face of his marriage breakdown. As in many things, his approach to the public interest in their relationship was different to that of Diana's."
Charles married Diana in 1981 but they divorced in 1996 and he later went on to wed Camilla, the Duchess of Cornwall, in 2005.