South Korea’s intelligence agency is using a sophisticated video analysis program to monitor the well-being of Kim Jong-un, the North Korean leader, apparently out of concern that a recurrence of his previous bouts of ill-health could trigger instability within the regime.

The National Intelligence Service delivered a briefing to members of the South Korean parliamentary intelligence committee this week in which it demonstrated how the program uses video and still images to create a three-dimensional picture of an individual and can monitor changes in their physique, the Yonhap news agency reported. Based on that information, experts are able to track changes in Mr Kim’s health and fitness.

Mr Kim, who is believed to be 35 years old, has had a number of health problems since inheriting the leadership of North Korea from his father, Kim Jong-il.

The dictator, who died in December 2011, also suffered from a number of illnesses linked to his appreciation of fine cuisine and French brandy, including diabetes and high blood pressure.

Kim Jong-un has put on weight since he assumed control of the impoverished nation and was walking with a limp and supported himself with a cane when he addressed a special session of the North Korean parliament in July 2014. Later that year, he disappeared for a number of weeks and was rumoured to be receiving treatment for an unspecified illness.