In a strategic move to counterbalance China's influence, Cambodia upgraded its 70-year diplomatic relationship with Japan to a comprehensive strategic partnership in 2023 — elevating Japan to a pivotal position in Cambodia's foreign relations. This heightened collaboration opens avenues for cooperation in economics, digital technology and security, providing Cambodia with leverage in the dynamics of the US–China strategic rivalry.

Just rehabilitating from a few decades of civil war and internal conflict, Cambodia sees herself as the developing country which is dependent much on the foreign assistance to develop economics and politics. Two countries—Japan and China— among the development partners of Cambodia have formed very good relation with Cambodia since 1997 by providing aid to Cambodia. However, the objectives, way and methods which both countries provide assistance to Cambodia is different. For Japan, Official Development Assistance (ODA) is given with the attachment of democracy, human right, good governance, and juridical and administrative reform. However, China’s assistance to Cambodia is known as “ no string attached” which means that she does not want to intervene to domestic affair of Cambodia due to the mutual respect and non-interference policy. This will raise doubts to researchers and scholars how much influence China and Japan’s aid is in Cambodia. Nevertheless, there are a few studies done for Japan’s and China’s assistance to Cambodia. Therefore, this entire research paper is going to answer this previous doubt by adding the relevancy of China and Japan’s assistance to Cambodia taking the economic and political perspectives using the aid alignment and political implication to approach the analysis. Our finding shows that though Japan’s aid is more relevant to Cambodia in term of social sector, economic sector, governance and administration, and democracy, China’s assistance seems to be relevant to Cambodia in term of foreign policy and transportation sector than Japan’s.

While the maritime states of Southeast Asia—Indonesia, Malaysia, Singapore, Brunei Darussalam, the Philippines, and Timor-Leste—are not in Cambodia’s immediate neighborhood, they remain of great importance for the study of Cambodia’s foreign relations. In the geostrategic context, Cambodia’s support for China has entangled Cambodia in China’s fractious South China Sea disputes with the maritime Southeast Asian claimant states of Indonesia, Malaysia, Brunei Darussalam, and the Philippines. Looking further back in history, the Association of Southeast Asian Nations (ASEAN), which counts the maritime Southeast Asian states of Indonesia, Malaysia, the Philippines, and Singapore among its founding members, was involved in the Cambodian civil war and peace process. Looking even further back in history, we find that the pre-colonial kingdoms of today’s Cambodia and maritime Southeast Asia had significant dealings with one another. It is from that early period that we shall begin our survey of Cambodia’s relations with maritime Southeast Asia.

A look at Cambodia’s history and present shows the multifaceted nature of its foreign relations and how the relations have shaped the political, socio-cultural and economic landscape of the Kingdom. In this regard, foreign relations, simply put the relations between Cambodia and other states or international institutions, have been a double-edged sword. On one side, there were conflicts, war and diplomatic tensions due to reasons of ideology and national interest, imperialism and mutual misunderstanding. A case in point is the Preah Vihear conflict between Thailand and Cambodia as well as the Indochina war in the 60s and bombardments against Cambodia in the 70s. On the other side, foreign relations have been a source of inspiration, cooperation and development. New political and economic ideas have been exchanged across borders and led to growth and prosperity. Common international environmental and security challenges have been tackled in a cooperative way sharing the same vision. There are countless examples buttressing the positive effects of cooperation like the UNTAC peace mission, the results of development cooperation and ASEAN. Even if it is not always easy to bring stakeholders together, to create a common basis of mutual understanding, to design cross border decision-making procedures or to overcome national interests and historical resentments, the avoidance of war and insecurity is worth all the efforts. Cambodia has, since 1991, deepened and extended its foreign relations with regional and international partners, always envisioning the relevance of national stability, national interests and sovereignty. It is due to the importance of Cambodia´s foreign relations that Konrad-Adenauer-Stiftung Cambodia, in cooperation with the editors of this book, decided to create a comprehensive source of information on the Foreign Relations in Regional and Global Contexts of the Kingdom of Cambodia. As there is, to-date, a limited number of publications available, this book serves as a useful guide into the different relations and dynamics between Cambodia and its diverse cooperation partners. The publication is a comprehensive and thought-provoking contribution to the academic field of foreign relations and international studies as well as to all interested people. One particular aim of the book has been to motivate Cambodian scholars and students to academically engage with research questions about the relations of Cambodia with other countries and contribute with their articles towards the analysis and general better understanding of Cambodia’s foreign relations. The book is structured in four main parts, namely the relations with neighboring countries and maritime southeast Asia, relations with regional and global powers, memberships in international organizations and economic integration and security policy. Articles about Cambodia’s relations with neighboring countries and maritime southeast Asia is mainly concentrating on the difficult position Cambodia has, being located in the middle of two strong countries: Thailand and Vietnam. To give a balanced view the editors and KAS chosen to give a platform for authors from both of these countries. This part of the book also enlightens Cambodia’s relations to Laos and in general the importance of relations to the neighboring countries in the context of ASEAN. Articles about Cambodia’s relations with regional and global powers, especially the bounds to the three superpowers China, United States and the Soviet Union/Russia is the central theme of the publication. The tensions and cooperation Cambodia had with these countries are interwoven with all other parts of the book. Other partner countries focused on are the European Union, Australia, Japan, South Korea, and India. These chapters give the reader an insight about the rapidly rising economic ties Cambodia is establishing. Furthermore, the publication contains articles about Cambodia’s membership in international organizations and economic integration and security cooperation. Articles introduce the reader to Cambodia’s role in the ASEAN and its relation to the United Nations. Economically and security wise the reader learns about Cambodia’s defense policy, the Greater Mekong Subregional Cooperation (GMS) and Cambodia’s integration in global economic and financial systems.

In 2020, Cambodia experienced its sharpest economic contraction in more than a quarter-century as COVID-19 crippled its tourism industry, hampered foreign investment, and reduced demand for exports from its crucial garment and textile sectors. Wary of simmering popular unrest, the government of long-serving Prime Minister Hun Sen sought to support the battered economy with one hand while stifling domestic political dissent with the other. Domestic crackdowns brought further erosion of Cambodia’s ties with the European Union, and relations with the United States and some Southeast Asian neighbors remained tense as Cambodia drifted closer into a dependent relationship with China.

China was recently described by the Prime Minister Hun Sen as Cambodia‟s “most trusted friend”. This claim might be proved by a flood of China‟s aid as well as her sharp growing trade and investments in the last decade, which put China the biggest donor and the largest investor. However, Cambodia-China relations stretch much longer than what we see at the present and might be even more complex in the old days. Hence, I begin to examine how their connections have developed over time, especially at each cross section of the Cold War and the post-Cold War periods. Then, I will study closely what made these two countries approach each other and became the strategic partners in Southeast Asia by classifying each party‟s interests into economic and strategic characteristics. This classification might, on one hand, project a clear picture of Cambodia‟s unequal status in the relations, and, on the other hand, illustrate its growing independence from China‟s influence. After all, the paper discusses how this bilateral relationship might have the implication on Cambodia‟s domestic politics and vice versa .From Cambodia‟s perspectives, I argues that their current relations might widen the economic inequality and make the situations of human rights worse in Cambodia so this pair of consequences would, in turn, have domino effects on their future relations through the declining strategic interests of Cambodia‟s government, particularly from the post-national election 2013 onwards.

Sino–Khmer relation has been under the spotlight since the South China Sea Arbitration and the second-time failure of the Association of Southeast Asian Nations to issue a communique on siding with the arbitration result. The historical development and its trajectory of Sino–Khmer bilateral relations then emerge as the core discourse in understanding Cambodia’s further development. Under China’s One Belt One Road initiative, specifically the Maritime Silk Road, Cambodia has synchronized as China’s most significant regional partner through comprehensive strategic cooperation. The article reviews how Cambodia’s political and economic development have paralleled China’s grand regional economic strategy or seemed an extension of China’s domestic production chain.