Australia was high on the list for Britain’s revamp of its alliances after Brexit, and the stormy geopolitical climate that followed has only reinforced the need for a more ambitious partnership. Looking ahead, public demonstrations of the strategic dimensions of the relationship are needed to ensure that citizens’ remain willing to invest in one another’s security and success.

Both countries have been grappling with the urgent security demands of their home regions, but the increasing awareness of the integration of the Euro-Atlantic and Indo-Pacific theatres has paved the way for greater cooperation. The long-standing friendship has gained a new strategic dimension through the free trade agreement that entered into force in 2023, Britain’s role as a conduit for Australian support to Ukraine, and, most importantly, the trilateral AUKUS security pact including the United States. This strategic uplift has been evident in the development of a landmark Defence and Security Cooperation Treaty, which includes a joint consultation clause and a Status of Forces Agreement, making it easier for their forces to operate together in their respective countries.

The healthy contemporary state of the bilateral partnership reflects a concerted mission to modernise relations after decades of drift. After Britain joined the European Economic Community in 1975, its trade relationship with Australia declined and the political narrative became limited to little more than platitudes of goodwill. Brexit prompted an enthusiastic tightening of the relationship, and now the deteriorating global security environment and instability within the Western alliance, putting a premium on trust and shared international outlooks, is bringing the two countries even closer together.

The new energy behind British-Australian relations brings government policy closer to public opinion. YouGov polling ^[1] indicates that 78 percent of Britons view Australia in positive terms, ranking the country second, behind Canada. Australia is consistently regarded favourably as a strategic ally, as an economic partner ^[2], as a source of immigration ^[3] and with strong cultural ties.

These positive attitudes inform the strength of British support for AUKUS. An ASPI study ^[4] I conducted this year found the pact was regarded favourably, particularly when it framed around resilience and deterrence outcomes. Overall, 55 percent of Britons believe that collaboration with allies on defence and security projects will help to make Britain safer. Similarly, 59 percent think that partnerships, such as AUKUS, which focus on developing cutting-edge technologies with allies, will help Britain compete with countries such as China. Although Britons are not entirely persuaded that AUKUS will succeed as a deterrent against Chinese aggression in the Indo-Pacific, 44 percent believe that it will.

While the lofty corridors of government international departments have not always been positively disposed towards public opinion as a diplomatic measure, citizens’ views are now shaping tangible policy outcomes. Citizens’ attitudes towards other nations determine their willingness to support the allocation of government attention towards those relationships, and, in times of crisis, their willingness to make sacrifices to support and defend another country.

European fatigue with the war in Ukraine has emphasised the importance of public consent in determining leaders’ ability to act decisively and to sustain commitments to other nations. As the threats posed by authoritarian powers, such as Russia and China, have become more evident, the question of whether a nation’s friends will directly contribute to efforts to compete with and deter adversaries is paramount. This is a lesson that European capitals and Washington are currently being forced to learn. Shifting moods in public opinion will affect political calculations regarding the distribution of diplomatic, economic and military resources.

As the Britain-Australia relationship evolves into a more substantive partnership, the geographical distance between the partners means a stronger effort will be needed to drive emotional contiguity. Historical relationships are important, but in times of conflict and scarcity, geography can matter more. The British government’s Strategic Defence Review ^[5], published in early June 2025, made clear that Britain is pursuing a NATO-first approach, recentring the Euro-Atlantic and elevating the Middle East to the level of the Indo-Pacific, noting it as a secondary priority region.

Britain and Australia must demonstrate a stake in each other’s home regions and primary adversaries. This is why it has been important for Australia to support Ukraine and attend vital Euro-Atlantic forums. Equally, Britain’s decision to send a carrier strike group into the Indo-Pacific this year emphasises that its conception of its interests and responsibilities extends beyond its home region. Through these actions, citizens in both countries are given the opportunity to see the rhetoric of common values in action.

For all its understandable emphasis on the urgency of the European security theatre, the Strategic Defence Review also highlighted the need to achieve scale and impact with like-minded allies to address pan-regional and global challenges. The review was notable for its presentation of China’s military build-up as a direct threat to Europe’s interests, noting that its growing masses of both conventional and nuclear weapons can reach Britain’s shores. It powerfully conveyed ^[6] that the proliferation of Chinese innovation to authoritarian states means that Britain will be fighting Chinese technology in any global theatre. In such a context, dogged regional prioritisation can leave blind spots and fail to address the true sources of power and disruption.

Britain and Australia share an interest in a resilient and open international order. They should seek opportunities to reinforce the effectiveness of international forums, and identify opportunities for regulatory alignment in areas such as technology, space and green innovation. Britain’s efforts to support Australia’s participation in the G7 and NATO forums, and Britain’s membership of the Comprehensive and Progressive Agreement for Trans-Pacific Partnership trading bloc, provide settings to advance such principles, alongside other regional partners.

Allied burden-sharing is also increasingly important in a time of scarce resources. There is significant potential for Britain to act as Australia’s gateway to Europe, and for Australia to do the same for Britain in parts of the Indo-Pacific, amplifying the collective impact of each other’s investments and ensuring they are directed where they are most needed.

The British-Australian relationship is in strong health, but there is ample potential to unlock even greater ambition to take it forward. In a turbulent era, it is vital for both nations to be ambitious about their alliances and affirm their value.

This article is part of a series about the Australia-UK strategic partnership. The British High Commission, Canberra, is supporting publication of the series, but the authors are responsible for the content.