# Japan, Indonesia and Australia Hold Their First Trilateral Defence Talks

The three ministers discussed a joint training facility on Morotai Island, weeks after Jakarta agreed to expand military ties with Beijing.

- Published: 2026-08-26T05:17:19.611Z
- Canonical: https://polylog.news/2026-08-26/japan-indonesia-and-australia-hold-their-first-trilateral-de
- Publisher: Polylog (Global desk)
- Section: geopolitics
- Sources: [The Japan Times](https://www.japantimes.co.jp/news/2026/08/26/japan/politics/japan-indonesia-australia-defense-ministers/), [Antara](https://en.antaranews.com/news/428496/jakarta-treaty-2026-to-shape-future-indonesia-australia-ties), [The Diplomat](https://thediplomat.com/2026/03/indonesia-and-australia-to-expand-security-cooperation-to-include-japan-png/)

The defence ministers of Japan, Australia and Indonesia held their first trilateral meeting, [The Japan Times reported](https://www.japantimes.co.jp/news/2026/08/26/japan/politics/japan-indonesia-australia-defense-ministers/), with Japan's Shinjiro Koizumi, Australia's Richard Marles and Indonesia's Sjafrie Sjamsoeddin agreeing to expand bilateral and three-way defence cooperation. They discussed upgrading infrastructure on Morotai Island in North Maluku into a joint training facility.

The meeting builds on the Treaty on Common Security signed by Indonesia and Australia in February, known as the Jakarta Treaty. Australian Foreign Minister Penny Wong [described the treaty as the framework that will shape the two countries' relationship](https://en.antaranews.com/news/428496/jakarta-treaty-2026-to-shape-future-indonesia-australia-ties). The two governments had already [signalled in March](https://thediplomat.com/2026/03/indonesia-and-australia-to-expand-security-cooperation-to-include-japan-png/) that they would extend the arrangement to Japan and to Papua New Guinea.

Jakarta is not choosing a single alignment. The trilateral talks come weeks after Indonesia agreed with China to strengthen military ties following joint naval exercises east of Taiwan, according to The Japan Times. Indonesia's approach places it inside two overlapping security frameworks at once, which is the defining feature of middle-power behaviour in the region.

For investors, the durable element is procurement. Treaties of this kind create joint facilities, interoperability requirements and equipment purchases that persist across changes of government, and they redirect defence spending toward whichever supplier the framework favours.

## What this means

Overlapping security arrangements convert diplomatic language into long-dated procurement and construction commitments, which is where defence contractors and infrastructure firms in Japan, Australia and Indonesia gain. The same overlap raises the difficulty of crisis management, because a state inside two frameworks owes obligations to parties on opposite sides of a dispute. Indonesia's simultaneous agreements with Canberra, Tokyo and Beijing show middle powers hedging rather than aligning, which spreads defence orders across more suppliers.

## What to watch

- Whether the Morotai Island facility receives budgeted funding in the three countries' defence estimates, the difference between a communique and a commitment.
- Indonesia's next equipment orders and whether they favour Japanese, Australian, Chinese or European suppliers, the clearest measure of where Jakarta's hedging actually points.
- Whether Papua New Guinea joins a parallel arrangement, which would extend the framework across the approaches to northern Australia.