Japanese Prime Minister Shinzo Abe and his Australian counterpart Malcolm Turnbull have pledged to deepen defence ties and hold more joint exercises as part of enhanced coordination on regional issues, such as tensions in the South China Sea.
After his meeting with Mr Turnbull in Sydney yesterday, Mr Abe said it was "more necessary than ever for Japan and Australia to play a leading role for regional peace".
The two nations signed a revised defence pact to enable their militaries to supply ammunition to each other. Previously, the deal covered only food and basic supplies.
Noting the "increasing uncertainty" on the political, security and economic scenes, Mr Abe said it was important to increase and promote the rule of law.
"It is important to guard and increase the robustness of the free, open and rules-based international order," he said via an interpreter. "We confirmed we would cooperate and step up cooperation in the area of defence and joint exercises."
Mr Abe's visit was largely seen as an attempt to bolster the partnership between both nations and promote continued US engagement in the region, following the election of Mr Donald Trump as president.
In a joint statement, the leaders committed to keep pursuing the Trans-Pacific Partnership (TPP), a regional trade agreement Mr Trump opposes. The agreement covers 12 nations, including Australia, Japan, the United States and Singapore, but not China.
Notably, the two leaders stressed that the TPP would offer not only economic but also "strategic benefits".
"The two leaders affirmed that Japan's and Australia's respective security alliances with the United States remain as relevant and important today as they have been for over six decades," the statement said.
"Japan and Australia will continue to work proactively, alongside the US and other like-minded countries, including India, to maintain the rules-based international order," it added.
Mr Abe is in the middle of a whirlwind four-nation tour - including the Philippines, Indonesia and Vietnam - to boost Japan's economic and security ties across the region.
This follows concerns in Tokyo about China's growing assertiveness and worries about the uncertainty of future ties with the US under Mr Trump.
In comments that would no doubt have pleased Mr Abe, Mr Turnbull made clear that Australia, like Japan, expected the US to continue its engagement with the region.
"For both of our nations, the US remains the cornerstone of our strategic and security arrangements, and our respective alliances with the US are as relevant and important today as they have ever been," he said.
"We will work closely with the incoming administration as we have been to advance the region's interests and our shared goals."
In addition to the enhanced defence logistics pact, the leaders said they had directed their respective defence ministers to pursue "deeper defence cooperation in 2017, including joint training, exercises, operations and capacity building". They said they wanted to reach a deal, as early as this year, to make it easier to hold joint operations and exercises.
Both said they supported "enhanced coordination" on issues such as tensions in the South China Sea and the nuclear ambitions of North Korea.
The boost in defence ties follows a hiccup in bilateral ties after Australia rejected a Japanese bid for its A$50 billion (S$53.5 billion) submarines project last year. Tokyo had reportedly received an informal promise from Mr Turnbull's predecessor Tony Abbott that it would win the contract. The bid went to the French.