The North Atlantic Treaty Organisation's focus has remained within its geographic patch in Europe and the Atlantic Ocean since its inception following the Second World War.

But experts say Russia's invasion of Ukraine and China's rising aggression has resulted in the body examining the world beyond its borders more closely in what they say is a "natural evolution".

US news organisation CNN reported last week Japan is in open talks with the multilateral organisation to set up a liaison office - the first of its kind in the region.

The shift to the Indo-Pacific could mean Australia's ties to the body will likely expand in the coming years as Prime Minister Anthony Albanese prepares to travel to Lithuania in July for NATO's next summit.

NATO's assistant secretary-general Baiba Braze, who visited Australia in April, said member states were keen to learn from the changing nature of threats in the region along with sharing their knowledge and expertise.

"That's why for Australia, and I think for NATO, this partnership is mutually important," she told The Canberra Times during her visit.

NATO's 31 member states count 29 countries in Europe and west Asia among them in addition to the US and Canada.

While Australia, Japan, South Korea and New Zealand cannot become members under the organisation's existing rules, they are recognised as NATO partners, known as the Asia-Pacific Four, or AP4.

Australian National University national security expert David Andrews said NATO had evolved from a pure military alliance since the end of the Cold War and its increasing interest in the region was more diplomatic in nature.

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"The very fact that Australia has an ambassador to NATO indicates that it's a bit more than just a pure military alliance," he said.

"Even though they're a long way away, geographically, economically, and politically, there are very strong ties from Europe into our part of the world."

Like the US, NATO sees China as a "big challenge" to global stability across trade and political security.

Ms Braze said the trade numbers showed how crucial it was for Australia and other like-minded partners to maintain stability.

"NATO does not define China as a threat, neither does Australia. It's indeed a challenge or, let's put it that way, China's behaviour is a challenge," Ms Braze said.

"We expect Australia to continue working as well as we do now, to obviously develop its own defence capabilities to be able to, if necessary, not only to deter but defend itself, to continue engaging with other partners in the region and [to make] sure that the region is stable, that it's open secure."

A potential regional office opening in Japan and more visits by NATO officials to Canberra is just the start of its "natural evolution", UNSW defence expert Professor Carl Thayer said.

Whether it's AUKUS, or the G20, or the Quad, the liberal world is again looking to multilateral partnerships for security as strategic competition turns to rising aggression.

"You cannot have a narrow geographic focus anymore - your security is interdependent globally because of cyber, because of space threats and because of hypersonic missiles," he said.

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The focus for now, however, remains deterrence, he said. European ships in the region are making their presence felt and maintaining interoperability between NATO members and partners.

"[The Indo-Pacific is] the lifeblood of the global economy. [Europe is] heavily trade dependent upon it, and any disruption to that trade would affect their economies immediately and disastrously - same with Australia," Professor Thayer said.

"The European countries are following through ... [and] making their presence felt to keep the sea lanes open.

"But in the sense of trying to indicate to China to deter them from using force against Taiwan."