A South Korean man has defected to North Korea, following in the footsteps of his political parents who also made a high-profile switch of allegiance in the 1980s, according to Pyongyang's state media.

Years of repression and poverty in the reclusive North have led around 30,000 people to flee to its democratic neighbour in the decades since the Korean War, but defections in the other direction are extremely rare.

Choe In-guk -- the son of former South Korean foreign minister Choe Dok-shin, who died in 1989, three years after moving to North Korea with his wife -- landed in Pyongyang on Saturday, reported state-run outlet Uriminzokkiri.