Author Perspective — The British Cession of Chagos Islands to Mauritius: A Strategic Territory in the Crosshairs of Virtue-Signaling
By Bepi Pezzulli
Introduction
After a mere 100 days in power, the Labour government has made the decision to cede sovereignty over the Chagos Islands—a British Overseas Territory (BOT)—to Mauritius, signaling a significant shift in the United Kingdom (UK)’s geopolitical stance. The move has raised critical questions about the implications of such actions for the UK’s strategic interests on the global stage. Maintaining sovereignty over the BOTs has been a pillar of the UK’s long-term strategic interest since the end of World War II, as they play a crucial role in securing vital trade routes and maritime resources, preserving British geopolitical influence in key regions like the Indian Ocean, Middle East, and Africa.
As most recently stated in the Integrated Review of Security, Defence, Development, and Foreign Policy (Integrated Review)—published under Boris Johnson’s government in March 2021—the strategic, military, and diplomatic value of the BOTs strengthens the UK’s position on the international stage. According to the Integrated Review, this relevance is reinforced by the need to counter China’s expansionism within the British sphere of influence, which poses a significant threat to the UK’s security architecture.
Far from being the result of political calculus, the surrender of strategic territory in peacetime reflects the current government’s desire to erase historical ties with the remnants of British imperial infrastructure, regardless of the implications for the nation’s international standing. Ostensibly, Prime Minister Sir Keir Starmer has aligned with an anti-Commonwealth sentiment gaining momentum among former British colonies, particularly in the Caribbean, where nations increasingly seek to distance themselves from colonial legacies. Barbados, in a historic move, transitioned to a republic in 2021, severing its constitutional link to the British monarchy. Jamaica has announced plans to achieve full independence from the Crown by 2025, with the Jamaican Prime Minister Andrew Holness emphasizing the country’s desire for constitutional autonomy.
Yet, this decision comes at a time of unprecedented global instability. China has significantly strengthened its presence in Africa, and in key island nations such as the Seychelles and Maldives. Through initiatives like the Belt and Road Initiative (BRI), Beijing has funded key infrastructure projects, such as Kenya’s Mombasa port and Ethiopia’s railway systems, solidifying trade routes and economic sway. In Djibouti, China’s first overseas military base established in 2017 grants it critical access to the Bab-el-Mandeb Strait. Additionally, ports like Gwadar in Pakistan and Hambantota in Sri Lanka are part of China’s “String of Pearls” strategy, securing key maritime locations to protect its trade routes. China’s power strategy involves long-term loans, infrastructure projects, and resource-based partnerships, often without Western-style governance conditions. This approach appeals to nations seeking investment and economic support, creating financial dependencies that enhance China’s leverage across these regions.
Meanwhile, Russia’s war in Ukraine has strained Western military and diplomatic resources, and the ongoing conflict in the Middle East is testing the resilience of international alliances.
In this volatile context, the Chagos Archipelago represents far more than a legal or moral issue—it is a British geographical stronghold essential to maintaining western military projection across multiple theaters of conflict.
Historical Context and Background
The status of the Chagos Archipelago has occasionally been the focus of international disputes between London and Mauritius. When Mauritius gained independence from the UK in 1968, it agreed to a previous settlement that explicitly waived any future claims to the Chagos Islands (The Lancaster House Agreement of September 23, 1965). The legal case was seemingly closed, but decades later, the issue resurfaced, with Mauritius attempting to reexamine historical claims, taking advantage of growing national momentum to assert full sovereignty, particularly as colonial-era disputes gained renewed global attention.
In February 2019, at the request of the United Nations General Assembly (UNGA), the International Court of Justice (ICJ) issued an advisory opinion declaring the UK’s administration of the Chagos Islands unlawful, citing violations of decolonization and self-determination principles. The ICJ emphasized that the separation of the islands from Mauritius in 1965 breached international law. While the opinion was non-binding, the UN General Assembly later endorsed it, urging the UK to transfer the islands to Mauritius. This marked a pivotal moment in the legal and diplomatic dispute over the Chagos Archipelago.
The UK rejected the court’s advisory opinion in May 2019, arguing that the islands were vital for military purposes, particularly due to the presence of the joint U.S.-UK military base on the island Diego Garcia. Diego Garcia serves as a strategic hub for U.S. forces, primarily the U.S. Navy and Air Force, facilitating operations in the Middle East and Asia. Diego Garcia played a key role in “Operation Enduring Freedom,” launched against the Taliban and Al-Qaeda targets in Afghanistan after the September 11 terrorist attacks on the United States.
The UK also claimed that the advisory opinion failed to take into account the Lancaster House Agreement. According to Christopher Howarth, a UK Parliament senior researcher, the whole idea of enforcing “pre-independence boundaries” is flawed, as this approach ignores the distinct histories and wishes of various territories to remain under British governance. For instance, Anguilla separated from St. Kitts before independence, having explicitly expressed its desire to stay British. Similarly, the British Virgin Islands were spun off from their neighbors within the British Leeward Islands, and the Cayman Islands broke away from Jamaica. “Would the ICJ say that was wrong and St. Kitts can claim the whole colonial unit? The Central African Federation was a short lived British creation, it broke up when Zambia gained independence. Can Zimbabwe claim it?” Howarth asks.
Legal Complexities and Constitutional Controversies
From a legal standpoint, the transfer of the Chagos Islands British Overseas Territory to Mauritius raises significant constitutional and sovereignty-related challenges. Central to this issue is the tension between the royal prerogative and parliamentary sovereignty. Under the royal prerogative, the Prime Minister holds authority delegated to the Government by the monarch over foreign affairs, including matters of treaty-making and territorial negotiations. However, in cases involving the transfer of sovereignty or the disposal of Crown land, particularly land that is considered a strategic asset, parliamentary involvement becomes essential. This principle has been established since the nineteenth century. The debate in Parliament on March 24, 1863, addressed whether the British Crown could transfer British territories without Parliament’s consent. The Solicitor General, Sir Roundell Palmer, clarified that parliamentary approval was generally unnecessary unless English common law had been applied or Parliament had legislated for those territories. In cases of colonies like the Chagos Islands, where English common law was established, consent from Parliament would be required.
Contrary to this principle, Starmer announced his decision during a parliamentary recess. This timing effectively shields the cabinet from scrutiny and parliamentary questions, allowing the handover to unfold with minimal accountability.
Chagossian Rights and Identity at Stake
As the archipelago has never been under Mauritian sovereignty, the islands’ settlement represents a unique case. They were separated from the Indian Ocean Colony that included Mauritius before the latter gained independence in 1968, meaning the islands were never an inherent part of the Mauritian state.
The Chagossians, the indigenous population, which was forcibly displaced from their islands between 1965 and 1973 to make way for the military base at Diego Garcia, faced significant legal and social challenges for decades. In response, the UK government granted rights of abode in the UK under the British Overseas Territories Act 2002, acknowledging the injustices of their forced removal. Subsequently in 2016, the Immigration Act allowed those born on the islands or their direct descendants to acquire British citizenship, thus reinforcing their ties to the UK and providing a pathway for many to claim their rights as British citizens.
Consequently, the proposed transfer of the Chagos Islands to Mauritius raises not only concerns for the Chagossian community, who risk losing their established connections to British citizenship, but also unintended legal consequences. For example, the UK government is grappling with the situation of Sri Lankan asylum seekers stranded on the islands. Due to potential legal implications surrounding their transfer under Mauritian rule, the government is now considering allowing them to relocate directly to the UK. Initially, Starmer had proposed deporting these migrants to St. Helena, but vocal protests have forced a reconsideration of this policy.
A Conflict with U.S. Strategic Interests
Diego Garcia is critical to projecting power across the Indian Ocean, Middle East, and Africa. The official U.S. policy on keeping military bases overseas emphasizes their role in deterrence, regional stability, and alliance reassurance. Under the Pentagon’s Global Defense Posture they are considered vital for responding to emerging threats and enhancing military readiness. The U.S. government has consistently rejected Mauritius’ claims to sovereignty over the Chagos Archipelago, maintaining that the issue should be addressed solely with the UK, which has held sovereignty since 1816. Despite multiple efforts by Mauritius to involve the U.S. in its negotiations with the UK, Washington has upheld this position for over 50 years.
By acceding to Mauritius’ demands, Starmer risks ceding geopolitical influence in a region increasingly contested by China. Mauritius has cultivated deep ties with Beijing. Most recently, the Mauritius-China Free Trade Agreement (FTA), which came into effect on January 1, 2021, aims to enhance economic cooperation and liberalize trade and investment between the two nations. It covers various sectors, particularly services, by removing restrictions in over 100 service sectors, including financial services and telecommunications. The FTA is designed to create a favorable environment for Mauritian firms, providing them with assured treatment and access to the dynamic Chinese market.
The American concern is that Mauritius could now leverage this territorial gain to expand China’s presence in the Indian Ocean. While the UK has retained a lease-back over Diego Garcia for an initial 99-year term, it does not prevent Mauritius from authorizing a Chinese military base nearby to counter the UK and U.S. presence in the archipelago—a prospect that would shift the regional balance of power, undermining both British and American interests. This potential scenario is alarming the incoming U.S. Republican administration. President-elect Donald Trump has reportedly instructed the presidential transition team to get legal advice on the issue, while close allies have made public statements. Florida Senator Marco Rubio, the President-elect’s pick for Secretary of State, said the transfer was “concerning as it would provide an opportunity for China to gain valuable intelligence on our naval support facility in Mauritius.” Additionally, Idaho Senator James Risch, who sits on the Senate Foreign Relations Committee, accused the Labour government of giving in to “Chinese lawfare” and “yielding to pressure from unaccountable international institutions like the ICJ at the expense of U.S. and UK strategic and military interests.” Trump’s nominee for national security adviser Mike Waltz has also been highly critical of the deal. Recently, Waltz said: “Should the UK cede control of the Chagos to Mauritius, I have no doubt that China will take advantage of the resulting vacuum.”
Legally, the Diego Garcia base remains a matter of bilateral UK-U.S. agreement under the 1966 UK-U.S. defense treaty, and Trump may consider vetoing the transfer on the basis that the move endangers the base’s use as a critical U.S. military installation.
Conclusion
The transfer of the Chagos Islands to Mauritius reflects a troubling miscalculation in balancing historical accountability with geopolitical necessity. In ceding this vital territory, the UK risks diminishing its strategic influence in the Indian Ocean while leaving a critical flank of Western defense vulnerable to external pressures, particularly from China.
Diego Garcia, a cornerstone of UK-U.S. military cooperation, underscores the archipelago’s enduring significance. Yet this decision prioritizes symbolic reparations over pragmatic statecraft, raising questions about the long-term impact on regional stability and the Chagossian community’s rights.
At a time of global uncertainty, such a move suggests an alarming departure from the UK’s traditionally measured approach to its strategic assets. The cession of Chagos, far from resolving historical disputes, leaves the UK’s role on the world stage weakened and its allies wary.
Bepi Pezzulli is a Solicitor of the Senior Courts of England and Wales, specializing in Global Governance. He currently serves as the Director of Research at Italia Atlantica. In 2024, he stood as the Reform UK parliamentary candidate for Finchley & Golders Green in the UK General Election.
sts-038-086-104 is by NASA Johnson and is licensed under CC BY-NC 2.0.
