Papua New Guinean university students will be able to apply to join the Australian Defence Force from next month under a $65 million trial that could eventually see thousands of overseas recruits bolster Australia's military strength.

The announcement was made at a high-level meeting between Australian and PNG ministers in Port Moresby today, as the countries progressed a landmark military alliance that entered into force in July.

As well as enabling both nations to recruit each other's citizens into their militaries, the Pukpuk Treaty obliges the neighbours to defend each other in the event of a military attack.

The first cohort of successful applicants is expected to be sworn in by late 2027 under a pilot program aimed at recruiting 100 young Papua New Guineans over the next two years.

While they will initially enlist on temporary visas, PNG nationals will eventually have to obtain Australian citizenship to continue serving in the ADF.

Moira Digori, a fourth-year political science student at the University of Papua New Guinea, said she was keen to apply.

"I am patriotic and I think it would probably weigh on my conscience a little, serving in another country's military without serving in the PNGDF first," she told the ABC.

"But again, the opportunity to have a better life and potentially have citizenship in Australia is quite appealing to me, and I think it would be appealing to a lot of other students as well. So I think that would outweigh my patriotism."

She expected a huge amount of interest when applications opened on November 16.

"The pull factor would be better financial stability and generally better living standards in Australia than there are currently in our country," she said.

Australian Deputy Prime Minister Richard Marles said the arrangement would benefit both nations.

Recruitment shortfalls have been a major concern for the ADF, although recruitment numbers have improved in recent years.

"The pilot program will have smaller numbers to begin with, to ensure the right processes are in place ahead of further expansion to develop a program that is sustainable and provides enduring value for both Australia and PNG," Mr Marles said.

The trial will cost the Australian government $65 million, with the aim of eventually expanding recruitment on a much larger scale.

Applications will initially be open to students and recent graduates from two major universities — the University of Papua New Guinea and Pacific Adventist University — in the cities of Port Moresby and Lae.

To be eligible, they must be between 18 and 25 years old and cannot have previously served in PNG's military, police force or any PNG government security institutions.

They will also face the same security requirements and standards as Australian citizens who apply to join the ADF.

Currently, non-Australian citizens from Five Eyes nations who are permanent residents living in Australia are able to apply to join the ADF.

The arrangement was recently expanded to include PNG citizens who have Australian permanent residency, with 40 applications currently being processed.