In much of the world, the role of the first lady is so public and accepted that is has become mundane. Not so in North Korea, the so-called "Hermit Kingdom", where the apperance of the supreme leader's wife came as a surprise on Wednesday.

Ri Sol-ju has been appearing with her husband Kim Jong-un in recent weeks, and after an amusement park visit, state media off-handedly confirmed on Wednesday that she was the 20-something Kim's wife.

South Korean media reporter that Ri was rumoured to have been a musician who once visited Pyongyang's wary southern neighbour.

Kim's father, former leader Kim Jong-il, who died in December, was famously private. The younger Kim appears to have ushered in a new era.

Caroline Malone reports.