The Abbott government has forged a deal to share military technology with Japan including joint research on "marine hydrodynamics" that could pave the way for the purchase of Japanese submarine designs.
On a visit to Tokyo that is likely to be watched closely in Beijing, Foreign Minister Julie Bishop and Defence Minister David Johnston confirmed with their Japanese counterparts the "substantial conclusion" on talks for closer defence ties and technology sharing.
The deal, which was kick-started during Prime Minister Tony Abbott's visit to Japan in April, will be finalised when his counterpart, Prime Minister Shinzo Abe visits Australia in the coming months.
It comes at a time of rising tensions between China and several of its neighbours, including Japan, and follows a landmark speech by Mr Abe a fortnight ago in which he signalled an intention for his country to play a stronger role in regional security. Australia has warmly welcomed that move.
Senator Johnston said in Tokyo that "there is a much higher temperature in this part of the world than many Australians understand".
Only on Wednesday, Japan lodged a protest after Chinese fighter jets flew "abnormally close" to Japanese military aircraft over the East China Sea.
Australia is looking hard at the Japanese Soryu class diesel electric submarine as a replacement for the Collins Class fleet.
Senator Johnston will tour one of the Japanese boats on Friday, though he continues to stress that German and French designs are also options.
"In terms of non-nuclear, diesel electric submarine, the Japanese submarine is very, very good indeed," he said.
"We are interested to carefully and sensitively seek Japanese assistance and guidance with respect to the way we should go forward in building our own submarine."
Japanese Defence Minister Itsunori Onodera said the joint research into marine hydrodynamics is expected to start next year. It would involved technologies that can be applied to "any kind of vessels, including submarines", he said.
In a clear swipe at Beijing's growing assertiveness in both the East China and South China seas, the four ministers reaffirmed their condemnation of "the use of force or coercion to unilaterally alter the status quo".
In response to a Japanese journalist's question about China's recent surprise naval drill close to Christmas Island, Ms Bishop said the People's Liberation Army ships were within their rights to sail through international waters.
But she pointedly added: "What we want to ensure is that there is deeper communications between the countries of the region ... What we must ensure is that all behaviour, all actions are in pursuit of peaceful purposes - nothing that could be seen as force or coercion or violence in any way."