“Each initiative is different, but the main goal is the same: Harness the unique strengths of highly capable democracies to address shared global challenges,” he told the NATO Summit Defense Industry Forum on July 9.

The latest initiative ties Australia, New Zealand, South Korea, and Japan to NATO’s changing focus and aim to modernise capabilities.

Mr. Sullivan said the group was overhauling its command structure so partner nations could “rapidly shift to [a] war footing” if needed and know where to take orders from.

Further, NATO will implement “regionally focused plans” to ensure the body has the weapons and force needed to confront threats from “any direction or even multiple directions at once.”

“This is about readiness,” he said. “Under the new model, allies will know how many troops they are expected to muster in a crisis—and how quickly. For example, within 10 days, allies could have 100,000 forces where they need to be.

“Within a month, that number would double. And in the ensuing weeks, it would grow to 500,000.

“That has never been done before. NATO has now done it.”

Mr. Sullivan said the alliance’s focus was about counteracting the military expansion from Russia, Iran, North Korea, and the Chinese Communist Party.

“What happens in Europe impacts the Indo-Pacific. What happens in the Indo-Pacific impacts Europe,” he said.

The “no limits” partnership between Moscow and Beijing has raised concerns that conflict in Ukraine could have ramifications in the Asia-Pacific.

“For us to think that we live in a sequestered part of the world that is not affected by those conflicts is, frankly, foolishness,” warned former Australian Attorney-General George Brandis, in a speech to the Australian National University.

Meanwhile, NATO Secretary General Jens Stoltenberg said the alliance would push for the 2 percent floor on defence spending to become a requirement going forward, not just an aspiration.

“This is a result of a collective decision and collective responsibility,” Mr. Stoltenberg said.