North Korea has held a military parade and rally in a central square in Pyongyang, the day before South Korea hosts the opening ceremony of the Pyeongchang Winter Olympics.

Kim Jong Un, dressed in a long black winter coat, was shown walking on a red carpet with his wife at the beginning of the event, which state-run television broadcast hours after it was over.

It began with thousands of goose-stepping troops lined up in Kim Il Sung Square to form words and slogans.

Virtually all foreign media were excluded from the event.

North Korea had said it would hold a big event to mark the 70th anniversary of the founding of its military. February 8 has been seen as a less important founding anniversary but made something of a comeback in 2015 and was elevated further this year in part because it is the 70th.

The Olympics were probably also a big factor. Kim has gone out of his way to make sure the North will hold attention throughout the Games.

Following a last-minute proposal during Kim's annual new year address, North Korea is sending 22 athletes to compete and a delegation of more than 400 musicians, singers, martial artists and members of a cheering group.

The North's conciliatory moves related to the Olympics have generally been welcomed in the South, but the parade was seen as more sensitive.

Though possibly best known for their legions of goose-stepping troops, North Korean military parades are the country's primary means of showing off its most recent advances in military technology - sometimes with aspirational mock-ups.

The North unveiled five new kinds of missiles at its most recent major military parade last April.