A documentary designed to portray North Korea as a workers' paradise has backfired on Pyongyang and is stirring up a diplomatic row with Moscow as well as a new bout of bad-feeling with Seoul.

Vitaly Mansky, a Russian film-maker, was commissioned by the North Korean government in 2014 to produce a documentary titled Under the Sun about the life of Ri Jin-mi, an eight-year-old girl who lives in Pyongyang.

Ms Ri had been selected, by the North Korean government, as a performer during celebrations to mark the Day of the Shining Star, the birthday of Kim Jong-il, the late dictator, and Mr Mansky was given access to her family, school and way of life in Pyongyang for one year.

The film was scripted by Korean officials who also chose the locations and cast the participants and officials retained full control of the script.

It quickly became apparent the degree of power the state wields over its citizens, with workers exhorted to show more enthusiasm for their tasks by Mr Mansky's minders and family members told what to say and how to say it.