But the new deal creates a standing legal framework to replace a system of one-off access negotiations:“I expect there will be an increase in the number of exercise drills,not only quantity but the quality will reach a new level,” Mr Yamagami said.

Possibilities,he said,included joint freedom of naval navigation patrols and air-to-air refuelling as well as humanitarian and disaster response operations.

“We will have interoperability increasing,more exchanges of personnel,which would lead to strengthened deterrence. We have to address attempts to overturn freedom of navigation and freedom of overflight.”

Asked whether joint naval freedom of navigation operations through waters claimed by China would be badged as such,Mr Yamagami said:“We don’t necessarily call it freedom of navigation. It’s like the Olympics[now under way in Beijing]. We didn’t call it a diplomatic boycott. But whether you name it or not,it’s a diplomatic boycott.”

Mr Morrison last month said the RAA would allow the two countries militaries to work “seamlessly” together.

The former head of Australian defence strategy,Peter Jennings of the Australian Strategic Policy Institute,said:“This is now. We certainly were able to get access to Japan in the past to do exercises. There was always a fair overhead of work to make that happen. The RAA takes that away and makes access easier and routinised.

“If there were no change in political will the RAA wouldn’t mean much. But I think the intent to use this is really a step-change in the type of defence interaction we have with them.”

Air-to-air refuelling,he said,for instance,“is something you only do with forces you are exceptionally close to and trust”.

Mr Yamagami drew Australian attention to the East China Sea,which lies between China,Japan and South Korea. It’s where China’s territorial claims clash with Japan’s holdings,chiefly over the Senkaku Islands which China calls the Diaoyu Islands. These also lie close to Taiwan.

“We are concerned about any escalation. To Australian leaders,I would like to stress the importance of the East China Sea,” he said.

“A lot has been said about the importance of the South China Sea to commerce. Look at the maritime traffic in the East China Sea. The three biggest destinations for Australian cargoes are China,Japan and South Korea. Almost every cargo to China and South Korea goes through the East China Sea,” and shipping to Japan’s eastern ports did too.

“The East China Sea may sound far from Australia but there is a lot at stake in the stability of the East China Sea.”

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