Australia's former foreign affairs chief has called on the Government to mitigate risk and seek new diplomatic opportunities after the election of United States President-elect Donald Trump.

Key points: Australia on the cusp of significant changes, Peter Varghese says

Australia on the cusp of significant changes, Peter Varghese says He says it's not clear whether Mr Trump will maintain foundational elements of US foreign policy

He says it's not clear whether Mr Trump will maintain foundational elements of US foreign policy Says Trump administration could complicate Australia's relationship with China

Peter Varghese, who retired as secretary of the Department of Foreign Affairs and Trade (DFAT) earlier this year, warned Mr Trump's election would take Australia into "uncharted waters".

"If the days of US primacy are drawing to a close — and I for one would not rush to a conclusion about that — we will need to adjust our policy settings," he said.

His speech to the Australia Institute of International Affairs comes after Labor's foreign affairs spokeswoman Penny Wong called for a reassessment of the US alliance, describing Mr Trump's election as "a change point".

Mr Varghese said Australia was on the cusp of significant changes that would test the Government's ability to navigate a more complicated world.

"Ultimately, Australia has to make its own way: not by going it alone or turning inwards or being distracted by a phony debate about whether we need an independent foreign policy," he said.

"[We should be] building the relationships, norms and institutions which can compensate for the loneliness of a long-distance middle power."

Prime Minister Malcolm Turnbull has moved to assure Australians the US will maintain its influence in the Asia-Pacific region, describing it as "manifestly in America's national interest" to do so.

But Mr Varghese said it was not clear whether Mr Trump would maintain the foundational elements of US foreign policy, many of which align with Australia's national interest.

"Many have rushed to give us the answers in the short period since Mr Trump's election, but the reality is we will simply have to wait to find out," Mr Varghese said.

"We can easily scare ourselves in the meantime, but that does not achieve much."

Trump could complicate Australia-China relationship

Mr Varghese called for "a clear-eyed view of the national interest", and an unsentimental understanding of geo-political changes.

"We cannot afford to be too narrow in where we put our foreign policy focus," he said.

"Australia is not a global power but we do have interests across the globe.

"Asia and the United States will always be central to our interests, but we also need to spread our risks and seek out other opportunities."

Mr Varghese, who is now chancellor of the University of Queensland, said a Trump administration could complicate Australia's relationship with China.

"If China continues to be dismissive of its international legal obligations in the South China Sea, it will inevitably become harder for Australia simultaneously to pursue our economic interests with China and our strategic interests with the US and in a rules based international system," he said.

Some defence analysts have warned that Mr Trump's election could have "serious ramifications" for Australia's security interests.