Intelligence experts are mystified as to how a South Korean-born Sydney man fell under the influence of the North Korean regime and allegedly began trying to sell weapons technology for the rogue state.

Key points: First person charged under Australia's Weapons of Mass Destruction Act

First person charged under Australia's Weapons of Mass Destruction Act Nation states probably the intended customers for missile technology

Nation states probably the intended customers for missile technology AFP says the accused "agent" had contact with senior ranks of the North Korean regime

Chan Han Choi, 59, has become the first person charged under Australia's Weapons of Mass Destruction Act.

He has also been charged with breaches of international and domestic sanctions, for allegedly attempting to sell North Korean missile guidance technology and coal on the black market to raise money for the regime.

"We believe this man participated in discussions about the sale of missile componentry from North Korea to other entities abroad as another attempt to try and raise revenue for the government in North Korea," Australian Federal Police Assistant Commissioner Neil Gaughan said.

"Through the actions of this man and the evidence we will put before the court, the AFP will be saying this man was a loyal agent of North Korea."

Nation states could have been the intended buyers

Police alleged Mr Choi was trying to sell North Korean coal to non-government buyers in Vietnam and Indonesia, but would not say who was allegedly attempting to buy the missile guidance technology.

Professor Greg Barton, from Deakin University, said it was likely that the end buyers would be nation states.

"Historically we've seen dealings between Pakistan and North Korea, Pakistan initially being involved in supplying technology," he said.

"But there are many parties that would be interested in looking at the North Korean technology.

"At the end of the day there has to be client that actually wants to use the technology, so the end client is likely to be a nation state."

'Under the sway of foreign intel'

Professor Barton also said it was possible there was an ongoing flow of technological information between North Korea, and Iran, which is pursuing its own nuclear program.

He likened the situation to the Cold War days.

"North Korea is nothing if not determined, and presumably there's a very interesting tale of how this person was persuaded," he said.

"It is a reminder of decades earlier when some people in the West became persuaded by Russian propaganda and turned to support Soviet Russia.

"This seems to be somebody coming under the sway of foreign intel and being persuaded to act in their name."

The Lowy Institute's director of international security, Euan Graham, said the case suggested that Kim Jong-un's regime relied on informal networks within Australia, as it has no embassy here.

"This may have been as good as it gets for Pyongyang, in order to fulfil that backroom economic function, whether it's over the table or under the table," he said.

"And in this case it appears to have been more under the table in terms of acting as an export platform and a way of generating hard currency, which is always near the top of North Korea's needs."