Japan could soon be able to use Australian missile ranges as part of bolstered security ties between the two countries.
Defence Minister Richard Marles held talks on Tuesday with his Japanese counterpart Shinjiro Koizumi in Canberra on Tuesday.
Mr Marles said discussions were well under way for allowing Japan to use Australian ranges for its own tests, such as for its hypersonic missile program.
"We have agreed to progress a better and enhanced arrangement between Australia and Japan for Japan's use of our missile ranges over the next decade across a range of missile capabilities," Mr Marles told reporters.
Mr Koizumi said it would be only the second time Japan would have a missile range arrangement with an ally, only behind the US.
"If the Japan Self Defence Forces are able to conduct test launches of stand-off missiles, such as hypersonic missiles in Australia, it would be a groundbreaking development," he said.
The meeting was the first time a minister had met with members of the Japanese government since Prime Minister Anthony Albanese came under fire for comments he made on a podcast about melons gifted to him by Japanese leader Sanae Takaichi.
"She brought two and they're beautiful," he said, while making a gesture with both hands in front of his chest.
The prime minister has rejected calls to apologise over the comments, insisting the relationship between Australia and Japan remained strong.
Mr Koizumi said the issue of the comments were not discussed in the meetings.
"Before I visited Australia, the Australian side already told the Japanese side ... that (Mr Albanese) did not mean it that way," he said.
The Japanese minister also confirmed he had spoken with Mr Albanese since arriving in Australia.
It comes as the federal police confirmed it would investigate the leaking of correspondence between Japanese and Australian diplomats about the melon comments.
Following controversy and media coverage in Australia of the melon comments, a letter from Japanese officials to their Australian counterparts noted there had been "sensationalised reporting" about the interview.
No action would be taken by the Japanese government over the incident, the letter said.
The correspondence was leaked to several media outlets.
The leaking prompted coalition frontbencher James Paterson to request an investigation by the federal police into how the leak of the correspondence took place.
In its response to Senator Paterson, the federal police confirmed it would examine the referral.
"The Australian Federal Police takes allegations of unauthorised disclosures of Commonwealth information seriously and assesses all reports in accordance with its legislative responsibilities and established investigative processes," the AFP letter said.
"Your correspondence has been referred to Special Investigations Command, where the material will be reviewed and an updated provided at an appropriate time."
