The United States is Australia's largest foreign direct investor and its second biggest trading partner.
President-elect Donald Trump is committed to enhancing US military power and maintaining its presence in Asia, Australia's prime minister said on Thursday after "warm and frank" talks with the maverick tycoon.
Under President Barack Obama, the United States has pursued a foreign policy "pivot" towards the Asia-Pacific, including stationing marines in Australia, against the background of Beijing's increasing assertiveness.
But there has been concern about what direction bombastic Republican Trump will take in foreign policy after he trash-talked US alliances during his acrimonious election campaign against Hillary Clinton.
Prime Minister Malcolm Turnbull, who like Trump has a business background, said the billionaire was "a deal maker and he will, I have no doubt, view the world in a very practical and pragmatic way".
During a telephone conversation, the pair "discussed the vital importance of the United States' continued strong presence in our region".
"Nations have enduring national interests and I have absolutely no doubt the commitment of the United States to the alliance, its presence in the region, its commitment to its allies and our neighbours will continue," Turnbull said.
"We agreed that that presence has been an absolutely essential foundation of the peace and stability that has enabled the remarkable growth and prosperity, the remarkable economic growth we have seen over the last 40 years."
Turnbull added that Trump, who will take control of the world's sole superpower in 10 weeks, was committed to expanding the US military as he faces up to security threats around the world.
"He is proposing a very substantial investment in the United States navy," he said.
While the two allies found common ground on security matters, it seems the sweeping Trans-Pacific Partnership (TPP) trade pact, which Australia supports, is doomed.
The deal between 12 Asia-Pacific countries has been signed but not yet ratified by lawmakers in the US and with Trump running his campaign on an anti-free trade message, Turnbull admitted it did not look good.
"We did discuss, briefly, the TPP and I explained why Australia supported its ratification to him," he said.
"We agreed that we could refer to the fact that we had had the discussion but I think his views on that treaty are well-known."
The United States is Australia's largest foreign direct investor and its second biggest trading partner.