On January 6th local time, Brazil, the host country of the BRICS countries in 2025, announced in a press release that Indonesia has become an official member of the BRICS. The Chinese Ministry of Foreign Affairs announced this heavyweight news late at night on the 6th, expressing warm congratulations to Indonesia. Why did Indonesia quickly become a BRICS partner not long ago? What will its accession bring to the BRICS family and global southern cooperation? The conditions for welcoming the new year are ripe. Starting from the first foreign ministers' meeting of China, Russia, India, and Brazil in 2006, the BRICS cooperation mechanism has gone through 19 years of development and experienced two expansions. After the first expansion, South Africa officially joined, and the BRICS countries became the BRICS nations. The second expansion took effect on January 1st last year, with Saudi Arabia, Egypt, the United Arab Emirates, Iran, and Ethiopia officially participating in BRICS cooperation, ushering in the era of "Greater BRICS Cooperation". At the same time, during Russia's presidency of the BRICS last year, another important process - the work of BRICS partner countries - was also being promoted. At the end of last year, all parties identified 9 countries as BRICS partner countries. Nine countries include Indonesia, Malaysia, Thailand, Belarus, Bolivia, Cuba, Kazakhstan, Uzbekistan, and Uganda. These countries officially became BRICS partners on January 1st this year. As can be seen from the above, Indonesia has just obtained the status of a partner country. Now it has become an official member again, and the outside world generally describes this "upgrade" as "unexpected". But according to Brazil and Russia, Indonesia's candidacy was initially approved as early as the 2023 BRICS summit. However, at that time, the Indonesian government requested to wait until after the 2024 presidential election for a series of considerations before discussing. In addition, with the BRICS countries focusing on creating new BRICS partner countries in 2024, Indonesia's accession has been put on hold. It was not until October 2024, when Prabowo became the President of Indonesia and the conditions were ripe, that the BRICS countries reconsidered Indonesia's accession demands. The Russian side revealed that Indonesian Foreign Minister Sujiyono specifically mentioned Indonesia's desire to join the BRICS cooperation mechanism during his participation in the BRICS Kazan Summit, viewing it as a "carrier for promoting the interests of developing countries in the global South". Therefore, in accordance with the guiding principles, standards, and procedures for the expansion process agreed upon in 2023, the BRICS countries unanimously agreed to make Indonesia a full member. Adding opportunities to BRICS cooperation, Indonesia's accession will have a positive impact on both the BRICS mechanism and the country itself. Indonesia has a population of over 280 million, making it the fourth most populous country in the world. The gross domestic product is about 1.4 trillion US dollars. For most of the past decade, Indonesia's annual economic growth rate has exceeded 5%, making it one of the most dynamic emerging markets in the world. Therefore, Indonesia's accession will first further expand the representativeness and influence of BRICS, and also mark the increasing attractiveness of BRICS cooperation. According to estimates, after Indonesia becomes a member of the BRICS countries, the proportion of the BRICS population in the world's total population is close to 47%. If the populations of BRICS partner countries are included, this proportion will exceed 50%. The economic size of BRICS will also further increase (the GDP of BRICS countries will account for about 35% of the world's total in 2023). Indonesia's accession also means the first expansion of BRICS countries into Southeast Asia, which is one of the most dynamic regions in the world economy. It has been noticed that in addition to Indonesia becoming a member of BRICS, Malaysia and Thailand have also become BRICS partner countries, which may have a direct impact on the closer relationship between BRICS and ASEAN. Southeast Asia itself is a region with a relatively high concentration of countries in the global South, and economic cooperation between BRICS, ASEAN, and the global South will be injected with new momentum. For Indonesia itself, joining the BRICS can also bring many opportunities. Indonesia's resources and agricultural advantages complement those of other BRICS members. If we join hands with China in infrastructure and digital economy, cooperate with Brazil in bioenergy, and collaborate with Russia in energy development and processing. Indonesia's industrial upgrading can draw on advanced experience and technology to promote the manufacturing industry towards high-end. Indonesia's international status will also be elevated, and it will participate in decision-making as a member of the BRICS countries on the international stage to better safeguard its own and regional interests. From a global perspective, Indonesia's accession to the BRICS is a powerful manifestation of the trend towards multipolarity in promoting global solidarity and cooperation in the South. On the 6th, the Chinese Ministry of Foreign Affairs pointed out that the BRICS family welcomed new members, which conforms to the historical trend of the collective rise of the global South. The expansion of BRICS countries has also enhanced the representativeness and fairness of global governance. Some analysts believe that the BRICS mechanism is an important platform for promoting solidarity and cooperation in the global South, breaking the monopoly of Western countries on rule making in traditional international mechanisms, bringing a more balanced perspective to global governance, and helping to shape a more fair and reasonable international order. Looking ahead to this year's BRICS cooperation, Brazil has announced priority work topics, including: developing a more efficient payment system; Collaborate with relevant parties of the 2025 United Nations Climate Change Conference held in Brazil to improve the financing structure for addressing climate change, and so on. All parties hope that Indonesia's accession can further promote the above-mentioned cooperation of BRICS, promote the high-quality development of the "Greater BRICS Cooperation", and bring new hope for building a multipolar world. (New Society)