Japan’s defence minister has condemned China’s growing military stockpile, describing its “huge arsenal” as a destabilising factor in the Indo-Pacific region. The remarks came as the United Kingdom and Japan signed an expanded security agreement, aimed at bolstering joint defence cooperation in the face of rising regional threats.
Speaking at a press conference in Tokyo, Defence Minister Yasukazu Hamada said that China’s military build-up, including its nuclear and missile capabilities, posed a “grave challenge” to the international order. He argued that Beijing’s lack of transparency and its aggressive posture in the South China Sea and East China Sea required a robust response from like-minded nations.
“China’s huge arsenal, which it continues to expand at a rapid pace, is a matter of profound concern for Japan and the broader international community,” Hamada said. “We must take concrete steps to deter any unilateral attempts to change the status quo by force.”
The minister’s statement accompanied the formalisation of a new defence pact between Japan and the UK. The agreement, signed by Hamada and UK Defence Secretary Ben Wallace, deepens existing ties by facilitating joint military exercises, intelligence sharing, and defence technology co-operation. The pact builds on a 2017 agreement that allowed for UK forces to deploy in Japan for the first time since the Second World War.
Wallace, who is visiting Tokyo, emphasised that the UK remained committed to the Indo-Pacific region even after its withdrawal from the European Union. He said the “unprecedented” security environment demanded closer partnerships.
“The UK is a responsible, reliable partner in Europe and beyond. We are standing with Japan to uphold the rules-based international system,” Wallace said. “The challenge presented by a more assertive China requires us to work together, not as adversaries but as allies.”
The expansion of the Anglo-Japanese defence relationship is the latest in a series of moves by both nations to counter Chinese influence. Japan has also deepened its alliance with the United States and Australia, while the UK has sought to re-engage with Asian security through forums such as the Five Power Defence Arrangements and AUKUS, the trilateral security pact with the US and Australia.
China responded to the announcements by defending its military development as “defensive in nature”. A foreign ministry spokesperson said that Beijing had been unjustly targeted by alarmist rhetoric, and that its weaponry was proportionate to its legitimate security needs.
“China has no intention of entering an arms race, but it will protect its sovereignty and territorial integrity,” the spokesperson said. “Any attempt to portray China as a threat is a disservice to regional peace and stability.”
Analysts argue that the UK-Japan pact signals a strategic shift for both nations. For Japan, it provides an additional layer of security beyond its bilateral alliance with the US. For the UK, it serves as a key demonstration of its “global Britain” post-Brexit ambitions, projecting influence in a region of growing economic and strategic importance.
The agreement includes provisions for joint development of defence equipment, such as fighter aircraft and missile systems, which could lessen Japan’s reliance on US technology. A British official noted that the deal would also create opportunities for British defence companies in Japan’s expanding military market.
Despite the deepening co-operation, both nations face domestic constraints. Japan’s pacifist constitution, while subject to reinterpretation, still limits the scope of its military operations abroad. The UK meanwhile is grappling with reduced defence budgets after years of austerity, raising questions about its capacity to sustain a meaningful presence in the Indo-Pacific.
Nevertheless, Hamada and Wallace expressed confidence that the partnership would endure. The two ministers agreed to hold further discussions on joint exercises in the East China Sea and to explore ways to enhance cybersecurity co-operation.
The growing alignment between Tokyo and London is viewed as part of a broader trend of democratic nations policing the global commons in response to authoritarian revisionism. As Wallace put it: “This is not about containment. It is about providing assurance to those who believe in freedom and the rule of law.”
