Buckingham Palace is considering taking legal action over leaked footage that shows the Queen as a child performing a Nazi salute with her family.
The Palace has launched an inquiry into how the 17-second black and white film came into the hands of The Sun newspaper.
It shows the Queen, aged six or seven, join the Queen Mother and her uncle Prince Edward in raising an arm in salute as she played alongside her younger sister, Princess Margaret.
It is understood that depending on the outcome of the investigation, the Palace will be looking at issues of copyright and possible criminality.
A source said the royal household is trying to ascertain where the film came from, who it came from and why it was handed over to the newspaper.
A Palace spokesman said: "It is disappointing that film, shot eight decades ago and apparently from Her Majesty's personal family archive, has been obtained and exploited in this manner."
The grainy footage from 1933 shows the Queen playing with a dog on the lawn in the gardens of Balmoral, The Sun claims, before she raises an arm to wave to the camera with Margaret.
The Queen Mother then makes a Nazi salute, and after glancing towards her mother the Queen mimics the gesture.
The Queen Mother repeats the salute, joined by Edward, and Margaret raises her left hand before the two children continue dancing and playing on the grass.
Some have criticised the newspaper's decision to publish the footage, and a Palace source said the pictures should be seen "in their proper context and time".
The source added: "The Queen is around six years of age at the time and entirely innocent of attaching any meaning to these gestures.
"The Queen and her family's service and dedication to the welfare of this nation during the war, and the 63 years the Queen has spent building relations between nations and peoples speaks for itself."
The Sun's managing editor Stig Abell said the footage was obtained by the newspaper "in a legitimate fashion" and that its publication was "not a criticism of the Queen or the Queen Mum".