Princess Diana’s brother Earl Spencer has revealed that he turned down a request from Netflix series The Crown to film at his family’s Althorp estate.

The upcoming fifth series of the royal drama stars Elizabeth Debicki as Diana, Princess of Wales, and will reportedly zoom in on her controversial 1995 Panorama interview with Martin Bashir.

The move to include the storyline comes after a report led by Lord Dyson concluded that the BBC covered up "deceitful behaviour" used by Bashir to secure the bombshell interview.

It concluded that the journalist was in “serious breach” of the BBC’s producer guidelines when he faked bank statements and showed them to Earl Spencer to gain access to the princess for the interview.

The findings resulted in Diana's eldest son Prince William calling for it to be never aired again.

Speaking to BBC Breakfast from the impressive countryside home in West Northamptonshire where he grew up with the late royal, 57-year-old Earl Spencer said about being approached by The Crown: “They applied. They wanted to shoot here. But I don’t really do that stuff.

“Actually, to be honest, I don’t watch The Crown so I just said: ‘Thank you but no thank you’.”

Asked about the Panorama investigation, he said that there remains “a long way to go” and did not rule out legal action.

He said: “Lord Dyson did a very good job. His brief was tiny. It was to look at a very specific area and there is still so much more to look at in the broader terms of who was responsible for what.

“How did it come to this? Did documents get hidden from view? All sorts of really important stuff, which is yet to come out.

“So, I see the Lord Dyson report as a very welcome development but there is still a long way to go with this.”

Drawn on how far he was willing take his investigation, Earl Spencer said: “That is the question and I have got people looking at that, and we will see.

“It is not going to end now. I am not saying that as some ugly threat. It just can’t stop now as there is still more to come out.”

Season 5 of The Crown is expected to begin streaming on Netflix next November.