Australia and Indonesia Ink Defence Pact to Respond Together to Security Threats

Australia and Indonesia will formalise a major defence treaty early next year, marking what Prime Minister Anthony Albanese called a “historic moment” in the neighbours’ 75-year relationship.

Standing beside Indonesian President Prabowo Subianto in Sydney, Albanese announced that negotiations on the long-awaited “Treaty on Common Security” had been finalised, with the formal signing expected in January 2026.

“This treaty will commit Australia and Indonesia to consult at a leader and ministerial level on a regular basis on matters of security, to identify and undertake mutually beneficial security activities,” the prime minister said.

“And if either or both countries’ security is threatened, to consult and consider what measures may be taken—either individually or jointly—to deal with those threats. This is a watershed moment.”

Albanese said the framework was modelled on the 1995 Keating–Soeharto Agreement on Maintaining Security, and builds on the 2006 Lombok Treaty and 2024 Defence Cooperation Agreement.

President Prabowo called it “an important treaty committing ourselves to close cooperation in the defence and security field,” reaffirming both nations’ “determination to maintain the best of relations in order to guarantee the security of our countries.”

Treaty Explained

Foreign Minister Penny Wong said the new Treaty on Common Security would be a “significant extension” of existing cooperation, reflecting “the deep trust and close friendship” between the two nations.

The treaty commits both countries to:

• Regular consultation at leader and ministerial level on security issues;

• Joint or individual responses if either party’s security is threatened; and

• Expanded cooperation on defence activities such as training, cyber defence, and maritime security.

“It sets out in formal terms our common interest in the peace and security of our region,” Wong said. “Through this treaty, we will take our cooperation to a new level, for the benefit of both our own security and that of the region.”

Part of a Regional Strategy

The deal with Jakarta is the fourth security treaty Australia has signed in recent months, part of a wider diplomatic effort to reinforce alliances across the Indo-Pacific amid ongoing competition from Beijing.

In October, Canberra struck a Joint Maritime Security Collaboration Roadmap with India to advance naval cooperation and renew the Joint Declaration on Defence and Security Cooperation.

That same month, it signed an Enhanced Defence Cooperation Agreement with Singapore, expanding reciprocal access to military facilities and deepening collaboration in defence science, logistics, and professional training.

And in September, Australia concluded the Mutual Defence Treaty with Papua New Guinea—the “Pukpuk Treaty”—formally committing both nations to act if one is attacked and broadening training and interoperability.

The new treaty with Indonesia also underscores Canberra’s response to the Chinese Communist Party’s (CCP) expanding military and economic influence in the Indo-Pacific.

Earlier this year, Albanese pledged $15 million over four years to enhance maritime cooperation with Indonesia, including a new annual dialogue on maritime security.

The initiative came amid reports—denied by Jakarta but published by defence journal Janes—that Russia had explored basing military aircraft in Indonesia’s easternmost province, heightening concerns over foreign involvement in the region.

To reinforce ties, Australia has committed $100 million to strengthen Indonesia’s health system, $3.5 million for anti-malaria drugs for its military, and $50 million through the Fund for Green Infrastructure to drive clean-energy investment.

Canberra is also backing Indonesia’s sovereign wealth fund, Danantara, in its bid to join the International Forum of Sovereign Wealth Funds.

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