Japan’s prime minister touched down in Australia on Sunday with a set of shared anxieties – about Trump, China and the fragility of supply chains that the two insular nations have long relied upon – to which she sought some small relief.

By the time she departed, Sanae Takaichi and Australian Prime Minister Anthony Albanese had signed an economic security pact, unlocked nearly US$1 billion in critical minerals funding and laid the groundwork for what observers describe as the most comprehensive defence arrangement the two have ever forged.

The centrepiece of her three-day visit was the Australia-Japan Joint Declaration on Economic Security Cooperation, which commits both governments to coordinating responses to economic coercion: a provision analysts say is aimed squarely at Beijing and Washington alike.

Under the agreement, Canberra has committed up to A$1.3 billion (US$935.8 million) in support for critical minerals projects with Japanese involvement, potentially supplying resources including nickel, graphite and rare earths to Tokyo.

“Australia and Japan are taking action to protect our economies from future economic shocks and uncertainty,” Albanese said in a statement.

“By working together, we will achieve more secure and resilient supply chains that will benefit Australian and Japanese businesses and consumers now and into the future.”

Ian Hall, a professor of international relations at Australia’s Griffith University, said Takaichi’s visit “very clearly” signalled that Tokyo wanted its partnership with Canberra to be “properly strategic”, driven by what he called “shared anxieties” about the behaviour of both US President Donald Trump and China, compounded by ongoing disruptions to energy supplies.