Japan and Australia agreed on a breakthrough defence pact on Tuesday facilitating reciprocal visits for training and operations.
The Reciprocal Access Agreement strengthens defence ties between the two U.S. allies at a time when China is asserting its role in the region and the United States is going through a leadership transition.
A legal framework allowing Japanese and Australian troops to visit each other's countries and conduct training and joint operations, it was agreed in principle by Japanese Prime Minister Yoshihide Suga and his Australian counterpart, Scott Morrison, who is visiting Tokyo.
"In the Indo-Pacific region, security and defence cooperation between Japan and Australia, which have the will and capacity to contribute to regional peace and stability, is becoming increasingly important," Suga told a joint news conference.
"I hereby announce that we reached an agreement in principle on a reciprocal access agreement, which had been negotiated to elevate security and defence cooperation between Japan and Australia to a new level."
It will be Japan's first agreement covering foreign military presence on its soil since a status of forces agreement in 1960 that allowed the United States to base warships, fighter jets and thousands of troops in and around Japan as part of an alliance that Washington describes as the bedrock of regional security.
"Our special strategic partnership became even stronger, in particular, because today we have taken a significant step forward in Japan and Australia reaching in-principle agreement on landmark defence treaty, the Reciprocal Access Agreement," Morrison said.
The countries have been negotiating the defence deal for six years.