Photo: DAVID GRAY/AFP via Getty Images
On September 17, Australia and Papua New Guinea (PNG) signed a mutual defense treaty known as the Pukpuk Treaty. “Pukpuk” is a local word in PNG for crocodile, and Canberra has touted the Pukpuk Treaty as a historic moment that has “elevated” Australian-PNG relations to unprecedented levels. The following questions examine what is so remarkable about this treaty, what it could mean for the geostrategic balance in the region, and what to watch for in the future of Australia-PNG relations.
Q1: What does the Pukpuk Treaty encompass—and is it really such a big deal?
A1: If anything, official statements coming out of the Albanese government undersell the true significance of the Pukpuk Treaty—PNG’s first alliance ever and Australia’s first since the 1951 Australia, New Zealand, and United States Security Treaty. Not only does this agreement establish mutual defense ties—and commitments—between Australia and its largest Pacific Island neighbor, but it also provides the architecture to vastly enhance the capacity of PNG’s defense forces through increased joint exercises, enhanced intelligence sharing, and allowing for up to 10,000 PNG troops to serve in the Australian Defense Force (ADF). Given the ADF’s recruitment challenges and PNG’s undermanned defense forces, the arrangement offers clear benefits for both nations.
The signing of the treaty is the culmination of years of diplomatic legwork by both countries to deepen security and cultural ties, a process that formally began in December 2023 with the two governments signing a security agreement that provided a framework to enhance the security relationship between the two countries. As a mutual defense treaty, the Pukpuk Treaty stands as both a continuation of previous aspects of the Australian-PNG relationship but also constitutes a fundamental change in the depth of that relationship.
Q2: How does this treaty fit into the broader strategic laydown in the Pacific?
A2: The less-emphasized significance of this treaty lies in its effect on the strategic landscape of the region. While neither side explicitly mentioned China during the treaty’s signing, the fact remains that this treaty represents a major geopolitical move by Australia, which has been more overtly prosecuting its security interests in the Pacific over the past several years.
While Australia’s increased focus on the Pacific is bipartisan in nature and reaches back nearly a decade, Canberra’s efforts accelerated markedly following the secret Solomon Islands–China security deal of 2022. This Solomon Islands–China security agreement (the text of which has not been released) represented a point of success for China, which has been steadily increasing its outreach to the Pacific over the past decade—potentially in an effort to establish a security foothold in the region. Australia’s 2024 National Defence Strategy clearly articulated the government’s alarm over Chinese ambitions in the Pacific, setting the groundwork for a series of agreements with security stipulations, including in Nauru, Tuvalu, and even via a rugby deal with PNG. The subtext behind all of these is limiting avenues for China to integrate into the security architecture of the Pacific region.
For PNG, which abides by a “friends to all” foreign policy, the imperative behind this treaty is much more pragmatic—a formalized commitment by its biggest security partner to the defense of PNG territory, and the opportunity to further professionalize its growing defense forces. While PNG Prime Minister James Marape has repeatedly emphasized that his country looks to Australia and other Western countries for its security relationships, he has just as adamantly maintained the importance of China as a key economic partner. And yet PNG’s proximity to Chinese harassment in the South China Sea and its location at the nexus of what would be any major contingency in the Indo-Pacific also likely informed the government’s decision to sign the Pukpuk Treaty. Its leaders are not ignorant of Chinese ambitions in the Pacific, nor is PNG immune to Chinese territorial incursions—as demonstrated when a Chinese drone flew unannounced into PNG territory during a Chinese naval deployment earlier this year, a blatant violation of PNG’s sovereignty. To walk this delicate balance, the PNG government has described the treaty as creating “one bigger fence that secures two houses that has its own yard space.” Such descriptions allow Marape to avoid describing the treaty as an arrangement aimed directly at China, and avoid antagonizing PNG’s Chinese partners, while still allowing the construction of a fence to define—and protect—PNG’s territorial integrity.
Q3: How does the treaty fit into Australia’s broader Pacific strategy?
A3: Australia’s strategy in the Pacific has shifted from one largely premised on development to increasingly privileging security. Canberra’s approach to dealing with its Pacific neighbors contains many different elements, including deepening engagement across the economic, development, infrastructure, and climate spaces, as well as enhancing labor mobility and people-to-people ties. And yet, over the past several years, and in direct, if often implicit, response to Beijing’s growing security connections in the region, Australia has elevated the importance of its own security relationships with the region, looking to cement its position as the regional partner of choice on all security matters. Canberra has actioned this imperative in a variety of ways, including through regional policing initiatives, deepening police training with several countries, explicitly elevating security in its bilateral relationships, and even in some cases, giving Canberra a veto power over Pacific islands’ security ties with other countries. Australia has also doubled down on working more closely with other external partners, such as New Zealand, Japan, and the United States.
Overall, this new approach amounts to both a direct response to China’s strategy and an attempt to outdo Beijing in what amounts to a geopolitical version of keep-away. As Penny Wong, Australia’s foreign minister, stated recently, China and Australia now find themselves locked in a “state of permanent contest” for influence in the Pacific.
Q4: What does this treaty mean for U.S. national security?
A4: Washington has a strong interest in ensuring China does not make significant gains in the Pacific island region. If Beijing were able to cement its influence in the Pacific, especially in the security realm, it would not only come at the expense of Washington but also of Canberra and Wellington. A permanent (or even semipermanent) Chinese foothold would allow Beijing to extend its presence in the Pacific and undercut U.S. access to the region, circumscribing freedom of movement for the United States and others in the vital cross-Pacific sea lanes—all while further strengthening Beijing’s tools of authoritarian control.
Australia’s long-standing view is that a hostile power occupying territory surrounding its northern approaches would be inimical to the nation’s interests. In this, Australia’s strategic imperative syncs with the United States’ geopolitical interests. In PNG, the region’s largest and most populous country by several orders of magnitude, this imperative has prompted significant actions by both countries. In 2023, the United States and PNG signed a Defense Cooperation Agreement, elevating defense ties between the nations and allowing the United States access for basing in the country. The Pukpuk Treaty complements U.S. efforts and takes the Australia-PNG relationship even further in cementing security ties.
However, the recent rollback of some U.S. engagement abroad is complicating this synergy. A growing perception of an unreliable and self-interested United States is lending credence to China’s assertions that the region should look to Beijing, not Washington, to uphold global rules and norms. Australia has to figure out how to calibrate its engagement with the region, not just to fill material gaps left by U.S. shortfalls, but, more critically, to counter Chinese messaging across the Pacific and stem any additional tailwinds on Chinese security initiatives.
Q5: What are the likely next steps for the Australian-PNG relationship?
A5: The treaty, which was signed by Australian Prime Minister Anthony Albanese and PNG Prime Minister James Marape on October 6, must next be approved by each country’s parliaments to take effect. While this looks likely, and the treaty’s immediate prospects appear bright, there are multiple outstanding questions regarding the scope of the treaty and next steps in the Australian-PNG relationship. Questions remain, however, on complex issues such as Bougainville’s upcoming referendum on its potential independence and the potential for tensions between Indonesia and PNG. If and to what extent Australia might be involved in such a conflict is not completely clear, although both Australia and PNG have worked to assuage concerns, especially with their large and important neighbor, Indonesia.
The real question, however, is how or if this treaty—which is truly unprecedented in the Pacific—will affect the current trajectory of increasing Chinese influence across the Pacific. China’s semi-successful campaign to exclude Taiwan from this year’s Pacific Islands Forum Leaders’ Meeting (PIFLM)—resulting in all dialogue and development partners being excluded—and a recent policing arrangement with Vanuatu show that China’s will and capacity to exert influence in the Pacific remains strong. Growing exhaustion on the push and pull of Great Power Competition may work in China’s favor, as China is increasingly seen as a reliable development partner versus a mercurial and unreliable United States, allowing it to promote itself as working purely in Pacific interests rather than playing at great power rivalry.
Increasing PNG’s capacity to act as a strong Melanesian and Pacific leader would work in Australia’s and the United States’ favor and bolster Pacific regionalism and stability. PNG, under its current prime minister, has proved one of the strongest proponents for maintaining a Pacific-led security architecture, oriented toward traditional Western partners. PNG has also demonstrated that it is willing to push back on Chinese manipulation of Pacific regionalism, such as when Marape advised the Solomon Islands to maintain the Pacific Islands Forum’s inclusive approach to this year’s PIFLM and stick to precedent—such as including development partner Taiwan.
Ultimately, much will depend on the degree to which Australia will be able to maximize the most practical aspects of this treaty, such as integrating PNG defense personnel into Australia’s own defense forces. Should this treaty really result in up to 10,000 PNG defense personnel serving in the ADF—a huge undertaking given that the current PNG defense force currently numbers under 4,000—this would reap enormous benefits for PNG’s ability to develop a capable, regional force able to assist with not just security assistance in the Pacific but also disaster assistance efforts as well. Likewise, this development could also fill significant gaps in Australia’s own defense recruitment efforts—especially at a time when Australia’s defense needs are only increasing.
Through the Pukpuk Treaty, Australia and PNG commit to “working together to support a peaceful, stable, prosperous region,” alluding to building up PNG’s capacity to take a more active and assertive role in the Pacific—perhaps even itself displacing Chinese forces or obviating the need for countries like Solomon Islands or Vanuatu to look outside the Pacific for their security needs. If the Pukpuk Treaty truly helps set PNG and the Australia-PNG relationship on that path, then it will benefit not just these two nations, but the broader Pacific region—including the United States.
Charles Edel is a senior adviser and the inaugural Australia Chair at the Center for Strategic and International Studies (CSIS) in Washington, D.C. Kathryn Paik is a deputy director and senior fellow with the Australia Chair at CSIS.
