All Eyes On Diego Garcia: Why Are Chagos Islands Controversial? Must Know Facts About Indian Ocean Power Dynamics

New Delhi: The Chagos Islands are a remote archipelago in the central Indian Ocean, roughly halfway between East Africa and Southeast Asia. They consist of more than 50 small coral islands spread across several atolls. For decades they have been administered by the United Kingdom as part of the British Indian Ocean Territory, though Mauritius has long claimed they rightfully belong to it.

Islands Strategic Importance

The largest island, Diego Garcia, hosts one of the world’s most strategically significant military bases, jointly operated by the United States and Britain. Its location allows aircraft and naval forces to reach the Middle East, East Africa and parts of Asia quickly, making it a key hub for surveillance, logistics and long-range missions.

The base has supported operations in conflicts such as the Gulf War, Afghanistan and Iraq. Because of its isolation, it is considered highly secure and ideal for sensitive military deployments. Analysts say only few other locations globally offer the same combination of distance from population centres and proximity to geopolitical hotspots.

Disputed Ownership 

The roots of the dispute go back to the 1960s, when Britain separated the islands from Mauritius before granting Mauritian independence in 1968. Britain then created a new territory and leased Diego Garcia to the United States for defence purposes.

Mauritius argues that the separation was illegal and violated international law. In 2019, the International Court of Justice issued an advisory opinion stating that Britain should end its administration of the islands “as rapidly as possible” and that Mauritius has a valid claim. While not legally binding, the ruling increased international pressure on Britain.

Adding to the controversy is the forced displacement of the indigenous Chagossian population between the late 1960s and early 1970s to make way for the military base. Many descendants still live in exile and continue to seek the right to return.

Recent UK-Mauritius Deal

In 2025, Britain agreed in principle to transfer sovereignty of the islands to Mauritius while keeping the Diego Garcia base under a long-term lease—reportedly around 99 years. British officials say the arrangement balances legal obligations with defence needs, ensuring continued Western military access.

Mauritius welcomed the agreement as a historic step toward restoring its territorial integrity. However, critics in Britain and the United States worry that leasing rather than owning such a strategic site could create future vulnerabilities if political relations shift.

Why has Donald Trump criticized the plan?

US president Donald Trump has publicly urged Prime Minister Keir Starmer not to proceed, calling the lease arrangement a “big mistake”. He argued that strategic territory should not be handed over and warned that the base might be needed if tensions escalate with Iran over its nuclear programme.

Trump suggested Diego Garcia could be crucial in any potential military action if diplomacy fails to revive limits similar to those set under the Joint Comprehensive Plan of Action. His comments highlight how the dispute is no longer only about colonial history but also about present-day global security calculations.

India’s Strategic Interest 

India is closely watching developments because of its strategic partnership with Mauritius and its broader Indian Ocean security interests. New Delhi has consistently backed Mauritius’s claim over the Chagos Islands at international forums, viewing the issue through the lens of decolonisation and regional stability.

India does not have any military base or defence rights in Chagos itself; however, its infrastructure partnership with Mauritius on Agalega Island enhances maritime monitoring capabilities in the western Indian Ocean. Strategically, India’s concern is ensuring that the future status of Chagos - especially the base on Diego Garcia - does not alter the regional balance of power or allow rival external actors to gain influence near critical sea lanes used for Indian trade and energy routes.

High-Level Talks to Shape the Islands Future

The next phase of the Chagos dispute will be decided through diplomacy. Officials from the United States and Mauritius are set to hold high-level talks from February 23-25 in Port Louis to discuss future security arrangements linked to the islands and the continued operation of the military base on Diego Garcia.

The discussions are expected to focus on how sovereignty transfer plans can proceed while ensuring uninterrupted strategic access for Western forces. The outcome could determine whether a long-term framework is created allowing military use of the base under Mauritian sovereignty. 

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