A battle of wills is erupting between Buckingham Palace and historians in the wake of a leaked home movie that sheds light on the British Royal Family's links to Hitler's regime in the 1930s.

The movie - which was published by the tabloid newspaper The Sun - is whetting the appetite for more from their private archive.

Historian Karina Urbach was asked by The Sun to have a look at the tape before publication. The black-and-white home movie, which Urbach believes was captured by King George VI, shows two small girls - Elizabeth and Margaret - as well as two adults - the Queen Mother and the Prince of Wales, who would later become King Edward the VIII.

"In the video, the uncle, the Prince of Wales, encourages the girls to do Hitler's salute," Urbach tells As It Happens guest host Laura Lynch. "The Queen Mother does one, and then the Prince of Wales also does a fascist salute."

Queen Elizabeth II would have been six or seven at the time the movie was made. "Of course, the problem isn't the children," says Urbach. "They are totally innocent and were manipulated to do this stupid thing."

While much is already known about Edward's connections to Hitler, Urbach is fascinated by this new window into the Queen Mother's early political opinions on the Nazi regime."We know that she behaved admirably once war broke out, but we also know that before that, she gave Hitler the benefit of the doubt."

"I would never say that she was a Nazi," adds Urbach. "In November of 1939, she said that she had no more illusions about Hitler. So I'm asking what were her illusions were before '39. I think that's a legitimate question to ask."

Urbach believes the leak was accidental, but she wants Buckingham Palace to consider releasing more of its closely guarded material.

Urbach says if historians work on anything after 1918, it is impossible to get access. She says only official biographers and other "trusted establishment figures" can view the archive.

Much of the Royal Family's private archive is kept in the Round Tower at Windsor Castle. It documents the whole history of the Royal Family, including Queen Victoria's private papers.

"There is a public duty to give access to political papers." She believes it's also possible to maintain the family's privacy in matters that are of no public interest.

Urbach imagines how long it will take the Royals to open up.

"I'm sure it will take us a decade."

You can read The Sun's original story here.