SYDNEY -- One of Australia's leading China experts said on Tuesday that the nation's move to join the Asian Infrastructure Investment Bank (AIIB) represented a historic shift in the Australian foreign policy.

Hugh White, a professor of strategic studies at the Strategic and Defence Studies Centre, Australian National University, said the AIIB was a very big deal for Asia's economic future, but the way its establishment has played out makes it an even bigger deal for Asia's changing political and strategic order.

White said Canberra's announcement last weekend that Australia will join the AIIB despite reservations from the United States may come to be seen as marking a historic shift in Australian foreign policy.

In a column in Fairfax Media, White wrote that Australia has for the first time unambiguously defied Washington. "The government might not admit it, but they quietly crossed a Rubicon on Sunday."

"We can see why the AIIB is so significant by looking both at why China has set it up, and why the United States has opposed it. "

"China's motives are partly economic, and the logic for this is clear. To reach its economic potential Asia needs to invest about $1 trillion each year over the next decade on infrastructure of all kinds."

"Existing outfits like the World Bank and the Asian Development Bank have neither the money nor the expertise to begin to meet this challenge."

"China alone has the money needed to get things moving and the expertise, built up through its extraordinary achievements in developing its own infrastructure over the past decade. No country in history has ever built so much, so quickly."

White said six months ago, when China first asked Australia and other countries to join the AIIB, US President Barack Obama hit the phones, asking them to say "no".

"Over the past couple of weeks, countries around the region and beyond, including close US allies like Britain, South Korea and Australia, have rejected America's concerns and agreed to join the AIIB, knowing full well what that means for Asia's political order. "

White said this is about recognizing that as wealth and power shifts in Asia, the region needs to build a new order that is dominated neither by the United States nor by China, but in which leadership is shared between them.

"Australia needs to contribute to that process, doing whatever we can to ensure it works out in our interest. Sunday's announcement was a vital first step."