Tuna First! How the UK betrayed the Chagossian people

The Government’s Justification for the Deal

In 1966 the UK made a commitment to Mauritius that it would transfer sovereignty of the Chagos Islands, but at a time of the UK’s choosing and not while Diego Garcia was being used as a military base. The UK has a long-term renewable agreement with the US for a joint base which is due to expire in 2036.

However, in 2019 the UN resolved, after requesting an advisory opinion from the ICJ, that the transfer should be immediate and it instructed its agencies to recognise the islands as part of Mauritian sovereign territory.

In 2022, following subsequent decisions taken by UN tribunals and other international bodies, the Government began sovereignty negotiations with Mauritius. These had largely been completed when the current government took office in 2024.

The Government began the negotiations because of four specific issues.
1) Universal Postal Union resolving that only Mauritius can run Chagos postal services.
2) The ITLOS judgement that the Chagos coastlines are Mauritian and determine its sea border.
3) This consequence of the above that the UK is no longer a full member Indian Ocean Tuna Commission (IOTC).4) The Comprehensive Nuclear-Test-Ban Treaty Organisation is required to recognise the islands as Mauritian, but the Chagos Islands contains three nuclear monitoring stations which the Government wants to retain

Furthermore:
1) The direction of travel could mean future decisions taken by international bodies that could create “serious real-world operational impacts for the Base. It could affect everything from secure communications and overflight clearances, to securing contractors with consequential heightening costs.”
2) The uncertainty also meant “the UK’s unique relationship with the US and its international reputation was also threatened.

The Flaws in the Governments Justification

1) Of the four issues that prompted the UK to begin negotiations only the CNTO is really important, and the transfer of sovereignty requires a specific agreement on this anyway. The deal also acknowledges the UK’s diminished role in the IOTC.
2) There are other diplomatic routes that can be used to address issues as they arise, without full transfer of sovereignty.
3) The Conservatives, who instigated the negotiations when in government, have now withdrawn their support on cost grounds. (Labour supported the negotiations, when in opposition).
4) The is no reference to rectifying the historical crimes against the Chagossian people in the justification for the deal.

Key Provisions of the Deal

• Sovereignty: Mauritius is recognized as sovereign over the entire Chagos Archipelago, including Diego Garcia.

• Military Base: Mauritius authorises the UK to exercise all rights necessary for the operation of the base, including joint UK-US operations, for 99 years.

• Limitations on UK Authority: The UK does not have authority over civil and criminal jurisdiction (except as needed for the base), issuance of coins and stamps, registration of births/deaths/marriages, postal services unrelated to the base, sovereignty over natural resources, environmental conservation, or regulation of unrelated commercial activities. Some rights can only be exercised by Mauritius with mutual agreement.

• Defence and Security: The UK retains full responsibility for the defence and security of Diego Garcia and the base. The UK and Mauritius agree to cooperate on maritime security and related issues. The UK and US have unrestricted access and operational rights for the base.

• Joint Commission: A UK-Mauritius Joint Commission is established to facilitate implementation of the treaty and resolve issues.

• Environmental and Social Provisions: The treaty includes commitments to environmental conservation, protection of biodiversity.

• Resettlement: Mauritius has permission to resettle the islands, excluding Diego Garcia. This does not specifically relate to Chagossians.

• Economic Partnership: The agreement outlines a framework for economic cooperation between the UK and Mauritius.

The Cost of the Deal
The UK government officially estimates the cost of the Chagos Islands sovereignty agreement at £3.4 billion, based on the net present value of £101 million annual payments over 99 years. This figure uses a 3.5% discount rate, a standard accounting method that reflects the current value of future expenditures. The figure nets off the current cost of managing the islands, which has been increasing rapidly of late. However, some argue that the actual cost of the deal could be significantly higher.

The government has not yet specified how it will fund the deal. A senior Treasury minister acknowledged that spending has not been allocated and will need to be managed within future budgets. There is also speculation that the increased defence spending announced by the Prime Minister could be used to cover the lease payments, although this has not been confirmed.

The agreement breaches the following aspects of international law

1. Compensation for Forced Displacement

Universal Declaration of Human Rights (UDHR, 1948)

• Article 13(2): “Everyone has the right to leave any country, including his own, and to return to his country."
  Article 17(2): “No one shall be arbitrarily deprived of his property.

The forced removal of Chagossians and denial of return violate both provisions, and under general human rights principles, victims are entitled to restitution and compensation. The refusal to allow Chagossians to return to Diego Garcia should be a breach of the UDHR.

However, this has been circumvented by perpetuating the lie spread by the UK Government in the 1960s that the Chagossians were revolving contract workers, not the descendants of African slaves with roots on the island dating back to the 18th century.

2. United Nations Principles on Reparation (2005)

"Basic Principles and Guidelines on the Right to a Remedy and Reparation" affirm that victims of gross human rights violations are entitled to: Restitution (restoring the original situation), Compensation (financial redress for damages), Rehabilitation Satisfaction and guarantees of non-repetition.

Chagossians fall squarely within this definition as a forcibly exiled population denied access to their homeland

3. The African Commission on Human and Peoples’ Rights (2006)

This found that the UK had violated several articles of the African Charter, including:

• Article 12 (freedom of movement and residence).

• Article 14 (right to property).

• Article 18(1) (protection of the family).

• Article 21 (right to natural resources).

The Commission stated that the UK was obligated to provide adequate compensation and facilitate return. This judgement was ignored and the issues have not been addressed within this deal.

4. The UN Declaration on the Rights of Indigenous Peoples

The deal does not recognise Chagossians as an indigenous people under the UN Declaration on the Rights of Indigenous Peoples (UNDRIP). Despite meeting the criteria, including:

• Longstanding connection to a specific territory (the Chagos Archipelago).

• Cultural and historical continuity, including language (Chagossian Creole), food traditions, and social structures.

• Collective identity and historical marginalization, particularly due to forced displacement and denial of return.

Rights Provided for under the UNDRIP include:

• Article 10: Indigenous peoples shall not be forcibly removed from their lands without free, prior, and informed consent, and fair compensation.

• Article 28: Right to redress, restitution, or compensation for lands and resources taken without consent.

The Trust Fund

The creation of the Trust Fund clearly identifies the Chagossians as a discrete group of people, and therefore an indigenous one. As such it should meet the requirements of Convention No. 169 (1989) of the International Labour Organisation (ILO). Specifically:

• Articles 6–7: Indigenous peoples must be consulted through representative institutions whenever legislative or administrative measures affect them.

• Articles 13–19: Governments must respect the relationship between Indigenous peoples and their ancestral lands.

• Articles 20–26: Equal treatment in employment, social security, health care, and housing.

The Trust Fund to be established for the benefit of the Chagossians is £40m, which is inconsequential compared to the £3.4b cost of the deal. The Trust Fund will be manged entirely by Mauritius. There is no specific definition of what a Chagossian is or any reference to Chagossians in other countries. Not all expelled Chagossians went to Mauritius and many have no connection to Mauritius. There are no directions on how it is to be spent or requirement to meet the requirements of the UNDRIP or ILO Convention 169. Furthermore, under the UK’s Nationality and Borders Act (2022) (NBA) people of Chagossian heritage are entitles to apply for British citizenship and many thousands have moved. It is beyond comprehension how the UK can meet it’s obligations to the UK based Chagossian community by handing a relatively small amount of money to a foreign country. UK Local authorities are being placed under a huge strain as a result of the NBA.

Employment Rights

Article 10 of the deal gives preferential treatment to Mauritian citizens and contractors at Diego Garcia. They will be employed “to the maximum extent practicable.” However, there is no specific preference given to the ancestors of those expelled. This clause looks like a treaty between two colonial powers, which ignores the rights of the people whose lands they are. It reads like a 19th century treaty, not a 21st century one.

Conclusion

This deal, forged behind closed doors and justified with bureaucratic trivialities like postal stamps and tuna quotas, stands as a damning indictment of both the UK government’s approach to foreign policy and its disregard for basic human rights. The Chagossians, wrongfully exiled, denied justice, and ignored in this treaty, remain victims of one of Britain's most shameful post-colonial legacies. Rather than righting historic wrongs, the UK has cemented them into a modern-day agreement that prioritises strategic convenience and international optics over moral responsibility. By failing to ensure restitution, recognition, and a right of return, and by placing token funding in the hands of a foreign government with no universal mandate to represent Chagossians, this deal is not a step forward but a missed opportunity cloaked in diplomacy. The betrayal is complete—not because the UK lacked the means to deliver justice, but because it lacked the will.