He suggested the Duke and Duchess of Windsor were harshly treated and said the decision to bar Wallis Simpson from the title Her Royal Highness was "extremely hard-line".
Edward VIII abdicated in 1936 over his love for the American divorcee and became Duke of Windsor but only he, and not his wife, was allowed to be addressed as Royal Highness.
Prince Edward said that his great-uncle "desperately wanted" his wife to be his equal and have the title.
In an interview with the historian Hugo Vickers, published by the Daily Mail, he said: "I think it was possibly stretching it a bit to prevent the Duchess from having the title. It's very easy for us to say that now but at the time feelings against them, especially her, were running high."
The Prince said that had the Palace been more conciliatory towards the Duchess and granted her the Royal Highness title, relations would have been easier between her and the Royal Family. "I have to say the policy that was adopted by the King's advisers was extremely hard-line." The Prince has written and will present a programme on his great-uncle, "Edward on Edward", to be broadcast on ITV on 23 April.
He said he did not need the Queen's permission to make the film but he had needed it to see private letters and papers. "I wasn't going to do it unless there was that support and backing, and that was readily given."
The Prince's comments on the use of the HRH title come when some critics have called for the Duchess of York to be stripped of it, while the Princess of Wales has said that she is prepared to surrender her HRH title as a concession to the Prince of Wales.
This year is the 60th anniversary of the Abdication Crisis and Prince Edward stressed the difference in attitudes: what is seen as a great love story now was seen as a matter of duty in the 1930s.
The Prince's portrait is more sympathetic than some recent reappraisals: it has been suggested the Duke could have been involved in a Nazi plot to put him back on the throne. "His decision to meet Hitler was to make a direct appeal to try to ensure peace. Of course he got nowhere," the Prince said.Reuse content