New Alliances in the Pacific: Australia and Papua New Guinea Sign Mutual Defense Treaty
- Isabella Licwinko
- 2 days ago
- 4 min read
In a historical agreement, Australia's Prime Minister, Anthony Albanese, and Papua New Guinea’s (PNG) Prime Minister, James Marape, signed the Pukpuk Treaty in the Australian Parliament House in Canberra, making this PNG’s first official alliance with any nation and Australia’s first alliance in over 70 years. Proposed by Papua New Guinea, this alliance intends to strengthen the bonds between the neighboring nations. This signing of this treaty occurred during an ongoing period of discourse that speculates there could be future conflict between China and U.S. or Australian backed nations, however, neither Australian or PNG leadership claim the treaty is reactionary to an immediate threat.
Pukpuk, the Tok Pisin word for crocodile, encapsulates the purpose of the mutual defense treaty, as crocodiles are widely a symbol of power and security within PNG. The treaty states that any armed attack on either Australia or Papua New Guinea will be seen as a threat to the security and peace of the other, and that any activities with a third-party do not undermine their alliance. Additionally, the document allows up to 10,000 PNG troops to serve in the Australian Defense Force as they seek to expand, as well as modernize their defense relationship.
On the issue, Prime Minister Albanese remarked that “Our Alliance is built on generations of mutual trust, and demonstrates our commitment to ensuring the Pacific remains peaceful, stable, and prosperous.”
The two prime ministers initially met on September 17 and agreed upon a joint communique for the proposed mutual defense treaty; they signed the treaty on October 6, 2025 in the Australian capital. Originally, the Pukpuk Treaty was meant to be signed in September, however, “Marape's cabinet failed to reach a quorum.” Controversy surrounding the mutual defense treaty is not isolated to PNG’s cabinet, as a variety of sources find the contents and broader context of the treaty disconcerting.
Backlash over the alliance largely came from officials and retired military personnel from Papua New Guinea, citing a potential violation of their nation’s constitution as their main point of contention. “[PNG has] an important principle … of not being aligned to any countries in the face of threat”, retired Major General Jerry Singiork added. Similarly, opposition leader Douglas Tomuriesa said Papua New Guinea "needs strong partnerships but not at the cost of our constitutional authority, legal protections for our citizens or independent decision-making.” These fears are rooted in the over 100-year-old colonial history between Papua New Guinea and Australia that remains controversial to this day.
Papua, the southern half of what is now PNG, became a British Protectorate through Australian colonization in 1906. In 1920, Australia gained control of New Guinea, the northeastern part of the island and a former German colony. They eventually became known as the Territories of Papua New Guinea in 1945 and were ruled by Australia as a colony until 1975, when they officially achieved independence. After decades of colonial rule, Papua New Guinea has not had any official alliances with other nations and are historically known as a “friend to all and enemy to none”, making their decision to propose this treaty even more shocking.
Additionally, the Pukpuk Treaty comes at a time of growing geopolitical tension in the Pacific Ocean due to China’s increasing sphere of influence. Beijing heavily discouraged PNG from signing the mutual defense treaty. Prior to Prime Minister Marape’s signing on October 6, the Chinese Embassy in Papua New Guinea encouraged their neighbor to the south to reconsider moving forward with the Pukpuk Treaty: “We hope that the PNG side will continue to uphold independence and self-reliance, properly handle issues bearing on its sovereignty and long-term interests.” Papua New Guinea stands as China’s largest trading partner among Pacific Island countries. Additionally, China is also the most threatening nation to Australia's influence in PNG considering their ongoing efforts to establish a foothold into the island’s economy, as seen in their desire for PNG’s untapped mineral resources.. According to the Australian Institute of Technology, “[China] seeks to drive PNG away politically from its traditional ally, Australia.”
The United States and Australia’s fears concerning China’s influence in the southern Pacific only increased in 2022 when the Solomon Islands signed a new security pact with the People’s Republic of China (PRC), allowing the PRC a foothold only 3,200 kilometers northeast of Australia. This pact allows Chinese personnel and police to patrol the Solomon Islands, while also giving them ports where PRC warships can refuel. In February 2025, the Cook Islands signed an agreement with China that intends to aid development for both nations in areas such as education, infrastructure, and mining.
In response to China’s backlash to the Pukpuk Treaty, Prime Minister Marape said, “This treaty was not conceived out of geopolitics or any other reason.” Although both nations claim that the timing of this treaty should not raise concern, rhetoric amongst geopolitical circles question their motives. Papua New Guinea serves as a mutually strategic ally for Australia, as well as the United States. In May 2023, Secretary of State Antony Blinken and Prime Minister Marape signed a new defense cooperation agreement and shiprider, providing even more cautionary protections for both the U.S. and PNG in the Pacific.
While the Pukpuk Treaty was signed by both PM Albanese and PM Marape, the treaty must be ratified by both nations’ governing bodies. As of October 3, PNG’s cabinet approved the treaty, but it still must go through the ratification process in Australia's parliament.
The break of Papua New Guinea’s longstanding international nonalignment signals a new age for Oceania’s foreign policies as the PNG asserts their independent wish to enhance national security, even if it entangles them into China and the West’s rivalry. In a “bandwagon effect”, the surrounding islands may follow suit in strengthening or establishing alliances with traditionally more powerful nations in order to not be left behind in a geopolitical sphere currently obsessed with taking clear sides. As tensions simmer, all nations—Papua New Guinea, Australia, the United States, China, and various Pacific Island countries—appear to be precautionarily gearing up for a boiling point.