The Papua New Guinea-Australia Mutual Defence Treaty, also known as the Pukpuk Treaty, was agreed upon between Papua New Guinea’s (PNG) Prime Minister James Marape and his Australian counterpart Anthony Albanese through a joint communique last month in Port Moresby on the eve of PNG’s 50th independence anniversary. The Pukpuk Treaty, anticipated to be signed by both prime ministers on Sept. 15, 2025 was delayed due to administrative failure at PNG’s cabinet to facilitate the endorsement process before the Defence Treaty could be formalized.
However, this week the two leaders signed the Pukpuk Treaty in Canberra after an executive approval of the Treaty by Marape’s cabinet last week. The Treaty now elevates the countries’ bilateral defense status to that of an alliance, with the provision that an armed attack on either of them would be an attack on both. For PNG this is historic, making it the first country in the Pacific to have its close neighbor as an ally. For Australia, this is its first alliance with a Pacific country since ANZUS with New Zealand and the US, more than 70 years ago.
PNG, through its successive governments in the last 50 years, had not taken such a bold diplomatic step to shift its bilateral defense cooperation from a partnership to an alliance with Australia or any of its bilateral partners. Since gaining political independence in 1975, the principle of “friends to all and enemies to none” has remained at the heart of PNG’s foreign policy decision-making and diplomacy, particularly on security—whether in national defense or policing. This foreign policy principle has not only defined PNG’s national interest and sovereignty but has also set the focus on how and why PNG conducts diplomacy with its bilateral partners, including Australia, on security matters. Prime Minister Marape also reiterated “friends to all” and “enemies to none” as the “dominant” foreign policy in PNG during a press conference with his Australian counterpart on Sept. 17, after the signing of the joint communiqué.
But Marape, in response to a series of questions during the press conference, also stated that he “[goes] to sleep every night worrying if someone [would] invade [his] country…” This raises the most serious question of sovereignty and non-alignment: Invasion from whom? Marape’s response may seem diplomatically odd but in practical terms it undermines PNG’s sovereignty and national interest and in the long term violates the principle of “non-alignment,” which PNG had long upheld as a sovereign state over the last five decades. Historically, PNG had only been invaded as a colony during the two world wars but not as an independent sovereign state since 1975 by any external powers.
Of course, the defense treaty was proposed by PNG and Australia was honored to agree to it during the initial stage of negotiation early this year in Canberra. But for Australia, there are bigger forces at play, particularly China as a rising regional player in the Pacific. The status quo is being challenged, particularly on regional leadership. With its partner-of-choice foreign policy in security cooperation for the Pacific countries envisioned in its National Defense Strategy, Canberra has tried as much as possible to curb China’s security influence in the Pacific after the 2022 Solomon Islands security pact with Beijing. Pat Conroy, Australia’s minister for defense industry and for Pacific Island affairs, who witnessed the signing of the Pukpuk Treaty, stated last October in Washington, DC that Canberra will use every tool of statecraft to ensure being the best partner of choice in the region, given that the country is already in a state of permanent contest for influence with China in the Pacific. Beijing in 2022 stated very clearly through its ministry of foreign affairs that it does not seek “spheres of influence” in the Pacific but would remain a direct stakeholder in the security of the South Pacific.
In 2023, for instance, PNG was urged by Australia—and Australia’s ally, the US—not to take China’s bilateral security offer on policing, as PNG already has a similar bilateral security arrangement with Australia and, for PNG and other Pacific countries, Canberra will remain the partner of choice in security cooperation, with Beijing for economic ties. The Albanese Labor government sealed a A$600 million (US$400 million) National Rugby League sports deal with PNG last year to ensure PNG does not enter into any bilateral security agreement with China. The signed Pukpuk Treaty could be seen as part of Canberra’s effort to drive its strategic interest in PNG and the broader Indo-Pacific against a rising China.
But regardless of the big power politics between Canberra and Beijing in security cooperation in the Pacific, the Mutual Defence Treaty enables PNG and Australia to address their shared security challenges and strengthen the capacities of their national defenses with respect to each other’s sovereignty and territorial integrity because it builds on their 1977 status of forces agreement. What remains uncertain is the “alliance” nature of the treaty. Marape, for instance, stated after the signing of the Pukpuk Treaty that PNG would remain “neutral” in the event of an Australia-China conflict given that there is a “high possibility” of its occurrence in the future.
The mutual nature of the treaty to advance and modernize the PNG Defence Force by Australia in the next 50 years and beyond is a positive development. But it should not have been agreed upon and signed for the purpose of forming a military alliance, because for PNG, the real threats are not from the outside, not even China, but from within. PNG should instead focus on developing its bilateral defense partnership with Australia, and its other external partners, to build its national defenses at the operational level to support the country’s policing and law enforcement efforts to address its internal security issues.
PacNet commentaries and responses represent the views of the respective authors. Alternative viewpoints are always welcomed and encouraged.
Moses Sakai ([email protected]) is a Research Fellow at the Papua New Guinea National Research Institute and a member of the Young Leaders Program of the Pacific Forum. In June-July 2024, Moses was a visiting scholar on US Foreign Policy at the University of Delaware under the US State Department’s Study of the US Institute (SUSI) for Scholars Program. He is also a Regional Research Associate (honorary) since August 2025 of the Indo-Pacific Studies Centre (IPSC), a Sydney-based foreign policy think tank in Australia.
Photo: Australia’s Prime Minister Anthony Albanese and Papua New Guinea’s Prime Minister James Marape sign the Pukpuk treaty at Parliament House in Canberra || Credit: David Gray/AFP