HE WAS a thorn in the Royals’ side for many years, famously prompting Prince Philip to suggest banishing him to the Tower of London.

Now photographer Ray Bellisario has put his treasure trove of more than 20,000 royal images up for auction, in the hope they will raise more than £500,000 for charity.

The 77-year-old, of Scott Gardens, Heston, began his career as a royal photographer almost by accident when, aged 18, he happened on the Queen sheltering under an umbrella on the rain-soaked streets of Truro, Cornwall.

He went on to capture thousands of candid images of the Royal Family, including exclusive photos of the Queen secretly meeting her uncle Edward the Duke of Windsor many years after his abdication – a reunion the palace had strongly denied.

His persistence saw him blacklisted by the palace, eventually leading to a ban on his photos being published in British papers, although he continued to sell them abroad.

His vast archive is due to go under the hammer on October 31, with the proceeds going to Reach for Rights, a charity he founded to provide free legal representation for those who could not otherwise afford it.

“Photographing the Royals never gave me any great pleasure but a lot of effort went into getting some of those photos and this auction will bring a sense of closure to that period,” he said.

Mr Bellisario, the son of Italian immigrant ice cream sellers, was born in 1936 in Pontefract, West Yorkshire, and was one of 13 children.

Not wanting to follow his siblings into the hairdressing trade, he left school aged just 14 and headed to London, where he landed a job as an apprentice with Fox Photos.

He says he never wanted to go into royal photography but as a young father with another child on the way, he saw it as a financial stop-gap. It would keep him in business until 1975, when, he explains, ‘we’d both had enough of each other’.

His collection includes rarely seen photos of a young Prince Charles waterskiing and the late Princess Margaret smoking, but it is a photo of Princess Anne taking a tumble of which he is proudest.

“She asked me ‘you’ve got thousands of photos of me. Why do you keep coming back?’,” he said.

“I told her I wanted one photo of her falling from her horse, and she replied ‘you’ll never see that’.

“I learned all about show jumping, so I could work out which jump was the most difficult and concentrate on that, and eventually all that work paid off.”

Mr Bellisario was never popular with the Royals, though he was on talking terms with many of them and had a soft spot for the late Queen Mother.

His official accreditation was withdrawn in the late 50s by his nemesis Commander Richard Colville, then royal press officer, who he says would instruct police to stand in the way of his shots.

But it was a picture of the Queen in a compromising moment, which he insists was captured accidentally, that got the blue blood boiling.

Taken in 1964 from a footpath looking out over the Queen’s Windsor estate, it prompted a Royal complaint to the Press Council, which banned the British media from publishing any of Mr Bellisario’s photos.

“The corgis had been yapping incessantly that day and Margaret, who had a short fuse, picked one of them up and threw it in the water, only to be ordered by the Queen to go in and get him,” he said.

“I sold the set of photos undeveloped and it was only when they were published that I realised one of them showed the Queen with her legs wide open, revealing her white underthings.”

Mr Bellisario continued to sell his royal photos overseas until 1975, before going on to photograph and report on affairs around the globe, including Nigeria and Cuba.

He has been described as the first British paparazzo but he objects strongly to the description, both on grounds of accuracy – the term was coined by Federico Fellini in the 1960 film La Dolce Vita, long after he first picked up a camera – and because he hates being compared with celebrity snappers, hanging around ‘seedy’ nightclubs.

He takes a certain pride in Prince Philip’s comment about sending him to the Tower, and relishes the irony of a staunch republican – he sticks his stamps on upside down – making his living through the Royal Family.

The Windsors themselves are rumoured to be among the potential bidders for the collection, also containing images of celebrities including Winston Churchill, which is due to be sold by Omega Auctions at east London’s Hoxton Arches.

Mr Bellisario, who has one granddaughter and 10 adopted grandchildren, still travels the globe as a photographer but is looking forward to devoting more time to his new charity.

“It’s important to me that people who often don’t know their rights, especially those who are discriminated against, are able to access the legal system,” he says.

“It’s also nice to think the royal family will effectively be helping to pay for that.”