Earl Spencer says he will feel “semi-vindicated” if he receives a BBC apology over the Panorama controversy.
The BBC has appointed Lord Dyson, a retired judge and former Master of the Rolls, to lead an investigation into the Diana, Princess of Wales interview which aired in 1995.
Diana’s brother Earl Spencer alleged that he was shown “false bank statements” by Panorama reporter Martin Bashir which were used to help him gain access to the princess.
“What I am saying is that, in my view, the BBC have very, very serious questions to answer on this and I was shocked and appalled.
“Diana always stood up for me a lot as my elder sister as a kid and I’m very happy to do this for her.
“And, ultimately, if I can get an apology out of the BBC for everything they did around this then I will feel semi-vindicated.”
Speaking about the controversy arising now, he said: “It’s a fair question, why wait 25 years?”
But he said that documents which came to light because of the anniversary of the interview “really shook me up”.
He alleged: “(The documents weren’t) just confirmation of what had happened behind the scenes but also who knew and why it hadn’t come out and why it hadn’t been dealt with.”
During the interview, Diana spoke candidly about her marital issues with the Prince of Wales. She famously alluded to his relationship with Camilla Parker-Bowles, saying: “Well, there were three of us in this marriage, so it was a bit crowded.”
She also questioned Charles’s suitability as king.
The Duke of Cambridge has welcomed the investigation, saying it “should help establish the truth behind the actions” that led to the programme.
The BBC says Diana wrote a note saying she did not see the false bank statements and that they played no part in her decision to give the interview.
The earl also repeated his criticism of Netflix drama The Crown, the lavish drama based on the life of the royal family.
“I think it would help The Crown an enormous amount if, at the beginning of each episode, it stated that: ‘This isn’t true but it is based around some real events’,” he said.
“Because then, everyone would understand it’s drama for drama’s sake.
“Obviously Netflix wants to make a lot of money and that’s why people are in the business of making these things.
“I worry people do think that this is gospel and that’s unfair.”