The Impacts of the Britain’s Agreement to Return Sovereignty over the Chagos Archipelago on International Dispute Resolution

Xinyi Zhang Zhongxiu Shen ^*

• Zhejiang Normal University, Jinhua, China

1 IntroductionAs reported on October 3, 2024, the governments of the Republic of Mauritius and the Britain gave an agreement on the Chagos Archipelago (hereinafter referred to as the Chagos), agreeing that Mauritius is sovereign over the Chagos. Mauritius can implement a resettlement programme for the Chagos former islanders, except the Diego Garcia, and the Britain will support those through measures such as the establishment of a trust fund. In addition, the Britain and Mauritius will strengthen economic security and environmental partnership building and work together to protect the ecology of the Chagos. Mauritius has seen this agreement as an important step towards completing decolonisation and paving the way for the return of the Chagos islanders to their homeland. The imperfection of the agreement is that Mauritius authorises the Britain to exercise the sovereign rights and authorities of Mauritius over Diego Garcia, the largest island in the Chagos, for an initial period of 99 years.The Chagos were administered by the Britain from 1814 to 1965 as a dependency of the colony of Mauritius. In 1965, the Prime Minister of Mauritius agreed the Chagos being separated from Mauritius. On 8 November 1965, the Britain established a new colony consisting of the Chagos and other islands, and on 30 December 1966 concluded the Agreement Concerning the Defence of the British Indian Ocean Territory with the United States, using it as a site for military bases and forcibly expelling the Chagos Islanders. After that, the United States built a military base on Diego Garcia. The evicted Chagos Islanders and their descendants took the Britain to the European Court of Human Rights. In its judgement, the Court found that the eviction of Islanders released by the Britain in the early 1970s constituted a crime against humanity. However, the Court declined to take up the case on the grounds that the applicants did not have proper victim status and had not been deprived of the benefit of a final and enforceable decision, and there was no indication of any arbitrariness or unfairness in these proceedings which could be construed as a denial of access to court. In June 2017, the United Nations General Assembly (hereinafter referred to as the UNGA) requested for an advisory opinion of the International Court of Justice (hereinafter referred to as the ICJ) on the legal consequences of the separation of the Chagos from Mauritius in 1965. In 2019, the ICJ stated in its advisory opinion that the Britain imposed an unlawful detachment on the Chagos and concluded that the Britain had an obligation to bring an end to its administration of the Chagos as rapidly as possible. The UNGA overwhelmingly passed a resolution demanding that the Britain should withdraw its colonial administration from the Chagos unconditionally within a period of no more than six months. Recently, Mauritian Prime Minister Nevin Ramgoolam and his government are looking to renegotiate three terms of the agreement, aiming to iron out the differences on sovereignty, lease terms and finances before signing the agreement.Although the issue of sovereignty of the Chagos has not been further resolved, the impact of the agreement to return the sovereignty of the Chagos on the international dispute settlement can be seen. This review explores in depth the impact of this event on three aspects: small powers, great powers and international dispute settlement institutions. After that, this review also analyzes de feasible ways to solve territorial sovereignty disputes with long history and complex sensitivity between States.2 The Impact of the British Agreement to Return Sovereignty over the Chagos on International Dispute Resolution2.1 Impact on Small Powers: emphasis on the concurrent use of multiple dispute resolution methodsThe event is of great significance and inspiration to small powers. Firstly, it marks the formal end of the British colonial era in Africa and sets an example for the decolonisation of the Global South. It not only strengthens the position of small powers in international law and relations, but also encourages other colonized States in their endeavors to claim their own sovereignty. Secondly, based on the agreement, Mauritius has the right to initiate the resettlement of Islanders, which is an important step forward from a human rights perspective. However, it was difficult to deal with the growing complexity of international disputes through legislative and judicial means alone. Mauritius has resorted to various means of dispute settlement, including diplomatic and political, while turning to international dispute resolution institutions such as the UNGA and the ICJ. The advisory opinion of the ICJ and the resolutions of the UNGA had laid a good foundation for the settlement of the dispute, and it was the combination of those methods and Mauritius' diplomatic and political means that had led to the current outcome. This inspires small powers to adopt a multi-dispute settlement approach when facing great powers, strengthen their trust in and reliance on international dispute resolution institutions, insist on the use of international judicial and legislative means, and pay attention to the role of non-legal means such as diplomacy and politics, so as to form a synergy of multi-dispute settlement.2.2 Impact on Great Powers: increase external pressure for non-compliance with the international rule of lawThe Britain, as a great power, complied with the ICJ advisory opinion and the UNGA resolution in this event in accordance with the United Nations Charter (hereinafter referred to as the UN Charter) and the principles of international law. This behaviour not only demonstrates the British sense of national responsibility and enhances the British influence in the international arena, but also provides a model for other great powers to comply with the international rule of law and assume responsibility for their international legal obligations. Even if a great power is not considered to be legally privileged under the principle of sovereign equality, the great power does not deny that it should still assume special obligations in the absence of legal privilege, one of the bases - in the view of the great power, or even the main basis - is the great power's moral perception of its own national identity, that being a great power should bear special obligations to the international community or to other states. By virtue of the substantial benefits they receive and their great capacity to act, great powers should be under a heavier obligation to observe the international rule of law and international rules than small powers. Although the reasons for Britain's relinquishment of sovereignty over the Chagos are manifold, including legal and diplomatic political pressures and general considerations of British internal policy, Britain's move inevitably serves as a model for other major powers. The pressure on some Western States to abide by the international rule of law and pay attention to the advisory opinions of the ICJ and the resolutions of the UNGA in international dispute issues such as territory and human rights has increased, limiting the abuse of the prerogatives as a major power, and reinforcing the legal and political obligations of major powers to abide by the international rule of law.2.3 To the international dispute resolution mechanism: manifest the role of the ICJ and the UNGAThe ICJ has fully exercised its advisory jurisdiction in this event. In addition to the UNGA and the Security Council which have the power to request the ICJ to give an advisory opinion on any legal question, three other organs of the United Nations as well as some organizations, have the power to request the Court to give an advisory opinion on legal questions arising within the scope of their activities. There is no express provision in international law concerning the binding effect of advisory opinions. Generally speaking, except in the case of an application by the Security Council under Article 25 of the UN Charter, advisory opinions are not legally binding, but are binding in fact. Advisory opinions play an important role in the system of the international law, but they are obviously different from the existing jurisprudence of the UN Charter and international laws. As the core document of the international law, the UN Charter has universal legal binding force and wide scope pf application. Advisory opinions provide more legal guidance and rulings to settle specific disputes. The jurisprudence of the ICJ has important precedent value in the international law, while advisory opinions are used more to interpret legal qustions. The British initiative in honoring the ICJ’s advisory opinions affirms the judicial attributes and legal authority of the advisory opinion in fact affecting the conduct of States, and upholds the important position and authority of the ICJ in resolving international disputes. Based on this, the ICJ can, through the exercise of contentious and advisory jurisdiction, form a jurisdictional synergy to more effectively maintain international peace and security, regulate the behaviour of States and promote the smooth resolution of international disputes. Indeed, this event can be seen as part of a broader trend, with the ICJ delivering a judgement allowing Russia to cease special military operations in the context of the Russian-Ukrainian conflict, and with deeper work being done in similar situations.The role of the UNGA is also further highlighted in this event. The UNGA adopted a resolution recognising the Chagos as an integral part of Mauritius and calling on the Britain to withdraw from the Chagos. This put tremendous diplomatic pressure on Britain and eventually led to the return of sovereignty over the Chagos. Although the resolution adopted by the UNGA is only a recommendation and has no legal effect according to Articles 12 and 14 of the UN Charter, it represents the general position of the international community and carries the weight of world public opinion on international issues and the moral authority of the world community. This is not the first time that the validity of a UNGA resolution and an ICJ advisory opinion has been recognized by the world. The reasoning of the advisory opinion in Dispute concerning delimitation of the maritime boundary between Mauritius and Maldives in the Indian Ocean combined with a UNGA resolution has the effect of an established face.Besides, the Britain’s compliance with the advisory opinion of ICJ contributes to the development of the international law, particularly in relation to the interpretation and application of international principles and rules. In its advisory opinion, the ICJ applied the principles of the international law, such as the right to self-determination, territorial integrity, non-interference and internationally wrongful acts, to conduct a comprehensive legal analysis of the issue of sovereignty over the Chagos between the Britain and Mauritius. For example, the ICJ made it clear that the decolonization process in Mauritius was not yet complete and that the separation of the Britain violated the principles of decolonization an the right to self-determination as enshrined in the UN Charter. This provides evidence for the interpretation and application of principles of decolonization an the right to self-determination, further clarifies the spirit of the principle of the right to self-determination, and promotes the practical development of the international law.3 DiscussionThis event is not only a great historical victory for the global decolonization movement, but also provides a reference for the peaceful settlement of territorial disputes between States. Although the agreement has not yet been formally signed and implemented, the territorial sovereignty dispute which has long-term history and complex sensitivity has been greatly promoted. It emphasizes that it is feasible to adopt multiple dispute settlement measures to resolve historic territorial sovereignty disputes under the advisory jurisdiction of the ICJ. States having remaining territorial sovereignty disputes can first request the ICJ to exercise its advisory jurisdiction, and then further bring lawsuits based on this opinion, while asserting their legitimate territorial rights and interests in diplomatic and political occasions. The reservation of military bases in the agreement reflects the contradiction in national interests between the Britain, the United States and Mauritius, requiring the continuous effect of traditional international dispute settlement institutions, and expecting more flexible non-litigation methods.