Footage showing the Queen performing a Nazi salute as a child could have been accidentally leaked by Buckingham Palace, it has been reported.
The edited clip showing Princess Elizabeth and her sister Margaret seconds after the incident was reportedly used in an exhibition at the Palace last year.
It may have been inadvertently released to a documentary maker after a flurry of requests for the unseen royal home movies, according to the Daily Telegraph.
Buckingham Palace is considering taking legal action over the footage. The Palace has launched an inquiry into how the 17-second black and white film came into the hands of The Sun newspaper.
A spokesman for Buckingham Palace said: "There is an inquiry going on to find the source of the footage and until that inquiry is completed we would not give out any further information."
It is understood that depending on the outcome of the investigation, the Palace will be looking at issues of copyright and possible criminality.
The grainy footage from 1933 shows the Queen, aged six or seven, 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 her uncle Prince Edward, the future King Edward VIII, 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, but a Palace source has said the pictures should be seen "in their proper context and time".