Prime Minister Scott Morrison has departed for the United States for a series of meetings culminating in the first face-to-face Quad leaders' summit.
The White House meeting of the leaders of the US, Australia, India and Japan comes as senior Morrison government figures and defence officials warn of a "deteriorating strategic environment" in the Indo-Pacific region.
A more assertive China flexing its diplomatic, trade and military muscle is a key driving force behind the Quad.
Mr Morrison will also meet with British Prime Minister Boris Johnson in Washington, after lsat week announcing a security pact between Australia, the UK and US known as AUKUS.
The prime minister said the trip was about keeping Australians safe.
"This is always about ensuring that Australia's sovereign interests will be put first to ensure that Australians here can live peacefully with the many others in our region," he said at Sydney Airport on Monday.
"That's what we desire as a peaceful and free nation."
The AUKUS agreement brought with it a deal to build at least eight nuclear-powered submarines to replace Australia's Collins-class vessels.
Mr Morrison said the government lifting defence spending to two per cent of gross domestic product sent a clear message.
"Australia will always look to others, but we will never have to leave it to others," he said.
"We'll be able to sit at the table with our partners and our friends to create a more secure and more stable world, particularly here in the Indo-Pacific."
It is expected the Quad leaders, who met virtually in March, will announce partnerships in the areas of COVID-19 vaccines production and supply, climate, and critical and emerging technologies.
There are fears China is using vaccine supply as a strategic tool in winning over governments in the region.
Foreign Minister Marise Payne, who was in Washington for ministerial talks last week, said nations struggling with the pandemic's impact on health and their economies needed confidence "there are options available".
"We are guided by the priorities of our partner countries as we support them in their recovery from COVID-19 through enhanced access to vaccines and strengthened health security infrastructure," she said.
"Our question is 'what do you need?' Not 'how can you serve our strategic interests?'."
The Quad leaders are expected to agree on further areas of cooperation to be worked on over the coming year.
Mr Morrison will address the United Nations General Assembly, but rather than travelling to New York it will be a prerecorded virtual speech.
In his first White House meeting with Joe Biden, the prime minister is expected to discuss regional security and the COVID-19 pandemic.
Mr Morrison is not expected to make any announcements on climate policy, as he and other leaders prepare for the COP26 talks in Glasgow in November.
© AAP 2021