The move follows ‘final warning legal letters’ sent to two freelance photographers, according to a report by Evening Standard royal editor Robert Jobson.

In the action, one of the photographers has reportedly been told to stop harassing and following Prince George and his nanny.

A later BBC News report adds that no legal action has yet been taken, though a photographer has been warned.

A statement reportedly issued by Prince William to the media, earlier today, says: ‘There is reason to suspect that the individual may have been placing Prince George under surveillance and monitoring his daily routines for a period of time.

‘The duke and duchess understand the particular public role that Prince George will one day inherit but, while he is young, he must be permitted to lead as ordinary a life as possible.’

A spokesman for Prince William could not be reached for comment when AP called Buckingham Palace, asking to be put through to his office.