Prime Minister Anthony Albanese has used his second day in office to signal Australia's ambitions on cutting emissions and reinforce its commitment to a free and open Indo-Pacific.
Mr Albanese met with US President Joe Biden, Japanese Prime Minister Fumio Kishida and Indian Prime Minister Narendra Modi on Tuesday for the second in-person Quad leaders' meeting, where discussions included countering China's increasing assertiveness in the region.
"The Solomons was discussed in the meeting, including the issue in which China is seeking to exert more influence in the Pacific," he told reporters in Tokyo following the meeting.
"Australia is responding to that, along with the US."
The Quad agreed to address the impacts of climate change across the region through $US50 billion ($A71 billion) of infrastructure assistance and investment in the Indo-Pacific over the next five years.
The measure helps counter Chinese debt-trap diplomacy, with the four countries pledging to assist countries to manage their "debt issues".
Mr Albanese also sought to differentiate from predecessor Scott Morrison on climate action, citing his government's target of reducing emissions by 43 per cent by 2030.
"We know that China is seeking to exert more influence in the Pacific and we know that climate change is such an important issue," he said.
"I share the view that this is a national security issue. Climate change is not just about the environment, it's about the shape of our economies, but also our national security going forward."
The stronger stance was reflected in the summit's official communique, which welcomed the Australian government's "commitment to stronger action on climate change".
The leaders' meeting also focused on establishing supply chain principles, including discussions about human rights after the US passed legislation in December banning imports from China's Xinjiang region.
Labor has pledged to strengthen the Modern Slavery Act to tackle risks in supply chains.
Foreign Minister Penny Wong said the positions of Quad countries on the issue were clear but didn't elaborate on whether Australia would push India to take a more definitive stance against Russia following human rights abuses in Ukraine.
India has been ambivalent in its condemnation of Russia, relying on the Kremlin for arms imports as it tries to stand up to a more assertive China along a contested northern border.
Speaking ahead of the meeting, President Biden said the partnership was about democracy against autocracy.
"We're navigating a dark hour in our shared history. The Russian brutal war against Ukraine has triggered a humanitarian catastrophe," he said.
"The fundamental principles of international order, territorial integrity and sovereignty, international law, human rights, must always be defended, regardless where they're violated in the world."
Mr Kishida also expressed dismay at the war in eastern Europe, saying the invasion of Ukraine was "a grave incident which has fundamentally shaken the rule of law".
"We cannot let the same thing happen in the Indo-Pacific region," he said.
A similar sentiment was expressed in bilateral talks between President Biden and Mr Albanese, with the pair discussing the ramifications of Russia's invasion in the Indo-Pacific.
"The leaders agreed on the importance of continued solidarity, including to ensure that no such event is ever repeated in the Indo-Pacific," a readout of their meeting states.
While not officially on the agenda, the US defence of Taiwan has also become a focus after Mr Biden said Washington would become militarily involved if China tried to take the small island by force.
The US provides defensive weapons to Taiwan but has not expressly committed to military intervention if China invaded.
Asked after the meeting if the comments were a change in US policy, Mr Biden said: "No."
He gave the same answer when asked to elaborate.
Mr Albanese reiterated Australia's stance towards Taiwan remained the same following the comments.
"Our position is there should be no unilateral change to the status quo. Our position has not changed."
Australia will host the third in-person Quad leaders summit in 2023.
Australian Associated Press
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