Japan: The United States of America has "a strong determination" to resolve the North Korean nuclear crisis using military action if necessary, one of Japan's most senior defence figures has said.

In saying so, former defence minister Satoshi Morimoto has brushed aside widespread expert views that the rogue regime will drift into becoming a full nuclear power because there is no plausible way to stop them. The remarks also reflect a powerful strain of thought in Japan that the situation cannot be allowed to limp along until Kim Jong-un gets what he wants.

The former defence minister told Fairfax Media the next few weeks will be a crucial period of high tension and brinkmanship on the peninsula.

"North Korea strongly insists the US has to accept the North as a nuclear power. The US cannot do anything like that. So Washington has no intention, absolutely no intention, to open the dialogue with North Korea this time," said Mr Morimoto, who now serves as a special adviser to current Defence Minister Itsunori Onodera and is influential and well-connected within the government of Shinzo Abe.