It is a rumour that has followed him for almost thirty years.
On Channel Seven's 'Sunday Night', Princess Diana's secret lover and former military officer James Hewitt looked down the barrel of the camera and addressed it directly.
"Are you Harry's father?" asked host Melissa Doyle.
"No, I'm not," Hewitt said.
The former officer, who served in the Queen's Life Guard regiment, first met Diana in 1986 when was employed to conduct her horse riding lessons.
He appeared on 'Sunday Night's exclusive feature that saw Melissa Doyle travel to the United Kingdom to commemorate twenty years since Princess Diana's death.
I think she was quite easy to fall in love with so really I think I can be forgiven for that.
Joining her former butler, Paul Burrell, her best friend Rosa Monckton and bodyguard Ken Wharfe, Hewitt was interviewed at his farm in Devon, in southwest England, where he spoke openly about his affair with the 'People's Princess'.
After their first meeting, Hewitt and Diana were romantically linked for five years during the late 1980s -- at a time when Prince Charles was also rumoured to be having an affair with his current wife, Camilla Parker-Bowles.
Hewitt recalled falling in love with the princess: "It's a gradual period and then, you know, suddenly you can't get enough of each other or see each other as much as you want," he said.
Speaking of their secret meetings, he spoke of "frivolity, escapism, walking, laughter and cooking. Me cooking and her washing up!"
"No I don't regret (meeting her). I regret some of the things that have been caused by that but not that at all. No way."
The pair were separated when Hewitt was deployed for service in the Gulf War -- although media speculation followed them.
Upon asking whether Hewitt was Prince Harry's biological father, Doyle persevered. "Why does that keep being repeated?" she asked.
"It sells papers... It's worse for him probably. Poor chap," Hewitt said.
Hewitt was joined by Diana's bodyguard Ken Wharfe who would sleep on a camp bed in the hallway during the pair's secret meetings.
"I didn't have a problem with it, I mean... you know, it was pretty obvious what was happening and again, it wasn't for me to moralise on this," Wharfe told Doyle.
"I didn't really have a view on it or inwardly. It was her life, their life. I was there for one specific reason. I would never let her down."
Hewitt, who was once offered more than $16 million for letters from Diana and two from a young Prince William, now reportedly lives a quiet life in Devon.
When asked about meeting Diana, he said he had no regrets.
"No I don't regret that. I regret some of the things that have been caused by that but not that at all. No way."
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