A British-born Electronics and Telecommunications engineer who settled in Australia after being adopted believes he is the love child of Prince Charles and Camilla and is heading to the country's High Court to try to force the heir to the throne and his wife to take a DNA test.

Simon Dorante-Day, 53, has admitted court clerks laughed when he first filed his papers and despite his breathtaking legal claim being thrown out three times already he is refusing to give up 'his 40 year search' for the truth about his birth parents.

He believes that his parentage will have been discussed by the Queen, Prince Charles, Prince William and Prince Harry at this month's Sandringham summit where the terms of Harry and Meghan's 'Megxit' deal were thrashed out. And last year he caused upset having claimed Princess Diana's death in Paris in August 1997 came after 'she was going to go public with it'. 

Simon claims his adoptive grandparents Winifred and Ernest worked for the Queen and Prince Philip as a cook and a gardener respectively and told him 'many times' that he was 'Charles and Camilla's child'. 

He said previously: ‘I know it sounds unbelievable, but anything I say is checkable... I’m simply a man looking for my biological parents, and every road has led me back to Camilla and Charles'.  

Mr Dorante was born in Gosport, Hampshire in April 1966 and was adopted when he was 18-months-old by Winifred and Ernest's  Karen and David Day. 

If his bizarre allegations are true, he would have had to have been conceived in 1965, when Charles was 17 and Camilla, 18, and he claims his Windsor-like cheek-bones and teeth, and 'Camilla-style hair', is compelling evidence his claims are true.

He even calls himself 'Prince Simon' on social media and his Facebook page is packed with posts where he matches his face from birth to today with Charles, Camilla and their children, with particular focus on Prince William and Tom Parker-Bowles.

The British national denies claims his story is 'bonkers' and 'bogus', including critics who point out that his eyes are brown but Charles and Camilla both have blue eyes.

One commentator who took him to task said: 'Two people who have blue eyes cannot produce a brown eyed person. How is that explained in your case Simon?'

The 53-year-old responded: 'That's been explained publicly Sue it's already out there - that's why they had to tamper with my eyes - exactly the point'.

He also says he has compelling evidence proving his claim but said online: 'As things are all part of the court case at the moment I can't discuss much further.' 

Simon Mr Dorante-Day, who now lives in Queensland, has spoken a number of times about his belief that he was put up for adoption by then 18-year-old Camilla Shand, which appears to have been secured via his adoptive grandparents who had worked for the royal family.

'My grandmother, who worked for the Queen, told me outright that I was Camilla and Charles' son many times,' he told New Idea.

His wife Elvianna told the magazine: ‘We believe that Camilla fell pregnant to Charles and that Camilla, with the help of her family and the royals, kept Simon until he was 18 months old.'