In the now-infamous chat with journalist Martin Bashir in 1995, Diana was asked if she thought she would 'ever become Queen'.
You can watch her response below:
Fans think it was in this moment that Diana predicted she wouldn't be Queen, with one person writing on Twitter: "Diana even acknowledged this. She can be ‘Queen of People’s Hearts’ in spirit. She was not going to be an official Queen or Queen Consort."
"Diana accepted she would never be Queen," another said. "She will always be (as wished) the 'Queen of people's hearts.' Let that be enough. Time to move on."
And a third said: "Diana will always be Queen of people's hearts & always will be remembered as that, when she gave that controversial 'Panorama' interview she outlined just that."
Another added: “'I'd like to be a queen of people's hearts but I don't see myself being queen of this country' - Diana, Princess of Wales."
Over the weekend, the Queen issued a message thanking the public and her family for their support during her 70-year reign. In it, she expressed her wishes for Camilla to be known as Queen Consort, once Prince Charles becomes King.
She wrote: "When, in the fullness of time, my son Charles becomes King, I know you will give him and his wife Camilla the same support that you have given me; and it is my sincere wish that, when the time comes, Camilla will be known as Queen Consort as she continues her own loyal service."