Diego Garcia Military Base and British Indian Ocean Territory Bill

Earl of Leicester Excerpts

Report stage
Monday 5th January 2026 Lords Chamber

[Lord Lilley (Con)]

My Lords, I apologise to the House for being absent for my amendments in the first group. I am grateful to my noble friend Lord Hannan for moving them on my behalf with, I am sure, greater elegance than I would have been able to bring. Were I a believer in conspiracy theories, I would imagine that President Macron and Prime Minister Starmer had got together to prevent me from returning to this House, but I am sure that they both have more serious issues, given their lack of popularity in their respective countries, than dealing with me.

My Amendment 14 seeks for the Government to negotiate guarantees from the Government of Mauritius that Mauritius will not enforce its duties under the Pelindaba treaty on the base of Diego Garcia and to ensure that, if it were to do so, the sovereignty of the base would revert to the UK. The Pelindaba treaty seems pretty clear that it excludes the use of any part of any African country. Mauritius counts itself as an African country. When it takes sovereignty of the Chagos Archipelago, which we count as part of Africa, it will preclude any of those countries from having any nuclear weapons or armaments on that territory. It would therefore be very difficult, on a simple reading of the Pelindaba treaty, for us to use that for our nuclear submarines or for any aircraft carrying nuclear weapons.

The Mauritius treaty, as it is written, says:

“Each party confirms that none of its existing international obligations or arrangements now in force or effect between it and any third party is in conflict with the provisions of this Agreement”.


If that means that the parties to the agreement intend to ignore any other agreements that they have that may conflict with this, that is all right with me, but the trouble is that it then goes on to say,

“nothing in this Agreement shall affect the status of existing international obligations or arrangements except as expressly provided for in this Agreement”.

That would appear to suggest that nothing in this agreement will override the Pelindaba treaty unless it is expressly stated in this agreement. It is not expressly stated.

I have every confidence in the two Ministers’ patriotism and that they would put the defence of this country manifestly above other minor considerations. I am sure that if it was left to them, we could rely on all this, and I could sit down and not pursue the argument further. But we know that this Government say that their highest priority is international law. If they are now saying that they are prepared to ignore legal agreements and enter into agreements with countries expressly on the basis that they ignore international agreements into which they have entered, we are in a difficult position. I notice the noble and learned Lord, Lord Hermer, is in his place. Perhaps he has come especially to give us assurances that he will not, in this instance, express the supremacy of international law, and that ultimately the sovereignty and independence of this country, its military defence and its alliance with the United States take priority over those matters. Now, if we can have that assurance, that is fine by me.

I appreciate that here we are dealing with very sensitive matters, and I do not expect the Minister to go into fine detail, but I would like the Government to give me greater assurance than I get from reading the treaty that the Pelindaba treaty is not going, at some future stage, to be cited by Mauritius as a reason why we cannot use nuclear-powered vessels or nuclear-equipped weapons, armaments and aircraft from the base. Unless we have that assurance, we must be rather worried.

[The Earl of Leicester (Con)]

My Lords, I, too, was detained in France so I was not able to speak to my first amendment, Amendment 20, but I shall speak to my Amendment 21 and I support all the others in this group. Amendment 21 basically seeks to ensure that the Secretary of State consults the UK’s AUKUS partners on the transfer of the sovereignty of the Diego Garcia base and that we get the written approval of the Governments of Australia and the USA and the opinions of the senior naval staff of all three partners.

AUKUS is central to the strategic defence review. Secretary of State John Healey states in the foreword to the SDR that

“the AUKUS programme … will allow us to grow our nuclear-powered attack submarine fleet to up to 12. This will reinforce our Continuous at Sea Deterrent … and position the UK to deliver the AUKUS partnership with the US and Australia”.

There have been a number of notable naval critics; indeed, one of them, the noble Lord, Admiral Lord West of Spithead, on the Government’s Benches, a former First Sea Lord and Security Minister, warned:

“The Government may genuinely believe that the base’s long-term future is ‘more secure under the agreement than without it’. But … How can the base–which serves as an indispensable naval, air, and intelligence asset–be more secure under the sovereignty of another nation, rather than under our own?”


In November last year, retired Rear-Admiral Chris Parry criticised the Government’s deal to transfer sovereignty of the Chagos to Mauritius. He described the decision as “the biggest strategic mistake” he has seen in his lifetime. In February last year, Commander Peters, a retired Royal Navy officer who led British forces at the joint UK-US base on Diego Garcia said that the base was currently “easily defended”, but:

“If the outer islands are under Mauritian control, China could quite happily start redeveloping them and installing all sorts of spying equipment that I think would affect the security of Diego Garcia”.

--- Later in debate ---

[The Minister of State, Ministry of Defence (Lord Coaker) (Lab)]

My Lords, it is a pleasure to get up for the first time on Report and address your Lordships on this important group dealing with security matters. I will try to come to some of the points that have been raised.

I will come to the point about the letter that the noble Baroness raised, but I will start with the challenge that she put at the end to explain how the Government are dealing with the position on the treaty from a security point of view. This answers some of the questions that have been asked, not least by the noble Lord, Lord Morrow, and I will not go into some of the operational points that have been made by him and others. However, on the security matters, I can say that if your Lordships look at the expressions of support for the security aspects of this treaty, all our major international allies and partners have supported the security arrangements. That is a fairly significant point for us to make and a fairly important point for the House to recognise.

To answer the noble Baroness, the noble Lord, Lord Morrow, and the noble Earl, Lord Leicester: President Trump expressed support for the Diego Garcia arrangements within the treaty. US Secretary Hegseth said:

“Diego Garcia is a vital military base for the US. The UK’s (very important) deal with Mauritius secures the operational capabilities of the base and key US national security interests in the region. We are confident the base is protected for many years ahead”.


That was not me but the US.

[The Earl of Leicester (Con)]

What is the US paying Britain for the lease? It is pretty clear why the Americans are supporting this: they are not having to shell out £34 billion.

[Lord Coaker (Lab)]

The US pays for the operations at the base and has done for many years. I say to the noble Earl that it is a fairly important policy that the Government have secured this to ensure the security of the base over the coming decades. I will come to AUKUS in a minute, but the noble Earl, the noble Lord, Lord Morrow, and other noble Lords have asked in their amendments how the treaty arrangements protect the security of the base. All I am doing is reading out what our crucial allies are saying about it. I am saying what they are saying about it. They are paying for the operation of the base. We have secured the future of the base, and they are supporting it. Secretary Rubio came out and supported the base as well.

People ask me how we have secured it—this is the challenge the noble Baroness put to me—and how we have ensured that we have secured the future of the base. We have secured it by ensuring that our major allies support it. I can only imagine what the noble Earl would say if I could not read out quotes from the US supporting what we are doing. The Five Eyes have all supported it. Of the AUKUS partners, Australia supports it as well as the US. Canada, Japan, Korea and India have supported it. I think that is an important position for the Government to be in. That is the context within which all the amendments should be considered.

I do not question the desire of noble Lords in their amendments to challenge the Government and to understand how effectively we have done that. All I am arguing before your Lordships is that, in the context of the treaty, the future of the base is secured. That is a fairly important statement for the Government to be able to make. I will come to the Pelindaba treaty when I come to the amendment from the noble Lord, Lord Lilley, and address the specifics that the noble Baroness raised.

Amendment 8 tabled by the noble Lord, Lord Callanan, requests a statement from the Secretary of State on base security. The treaty has robust security provisions to protect the base, including full operational control of Diego Garcia, full UK control over the presence of foreign security forces across the archipelago and an effective veto over any construction or development that risks undermining, prejudicing or otherwise interfering with the long-term, secure and effective operation of the base on Diego Garcia. Claims that Mauritius is an unreliable partner and one that cannot be trusted are unfounded. Mauritius is a member of the Commonwealth and a westward-facing country with shared democratic values. Mauritius ranks among the top African nations in governance, human development and innovation. It is a full democracy, a regional leader in human rights and a trusted partner in upholding the rules-based international order, ranking second out of 54 African countries in the Mo Ibrahim Index of African Governance.

I thank the noble Lord, Lord Lilley, for tabling Amendment 14 and the noble Baroness, Lady Goldie, for supporting him. The noble Baroness asked me—I hope this helps the noble Lord, Lord Lilley, as well; I always try to be helpful, as noble Lords know—to ask my officials to draft a letter between now and Third Reading. Of course I will do that. I cannot guarantee that the content will necessarily be everything that the noble Baroness or the noble Lord want, but asking for a letter is a perfectly reasonable request. That will be done, and I will place a copy of it in the Library so that it is available to all noble Lords to consider as we move towards Third Reading.

Regarding the amendment tabled by the noble Lord, Lord Lilley, he knows—he has been a senior Minister and has a distinguished former Prime Minister sitting next to him—that it is very difficult to answer some of the specific questions that noble Lords have posed about certain capabilities. The noble Baroness, Lady Goldie, recognised that we cannot talk about it. I will say what I can. Amendment 14 tabled by the noble Lord, Lord Lilley, would require guarantees

“that Mauritius will not enforce its duties under the Pelindaba Treaty on the Base”

and that sovereignty would revert to the UK if it did. As I said in Committee, the Governments of the UK and Mauritius are both satisfied that the Diego Garcia treaty is compatible with their existing obligations under applicable international law. The UK will ensure that all operations on Diego Garcia comply with its existing obligations. The UK is not a party to the Pelindaba treaty, although it is a party to Protocols I and II. The treaty and the Bill will allow the base to operate as it always has. It will not reduce our ability to deploy the full range of advanced military capabilities to and from Diego Garcia in any way.

Diego Garcia Military Base and British Indian Ocean Territory Bill

Earl of Leicester Excerpts

Committee stage
Tuesday 25th November 2025 Lords Chamber

[Baroness Chapman of Darlington (Lab)]

The legal situation is as I have described. The noble Baroness may wish that that were not the case, but the legal position is as it is, and the Government do not intend to amend the Bill in order to change that legal position.

[The Earl of Leicester (Con)]

That legal position is guidance; it is not law.

[Baroness Chapman of Darlington (Lab)]

There have been legal judgments in English courts and elsewhere that have established that the right that the noble Baroness’s amendment seeks to grant to the Chagossian people does not currently exist in law. It is not guidance. Those are decisions of English courts. I hope that, with that, the noble Lord will feel able to withdraw his amendment.

--- Later in debate ---

[Lord Lilley (Con)]

My Lords, I will speak to Amendments 20T and 81K. Amendment 20T just requires that Amendment 81K would happen before the treaty, or parts of it, comes into force.

Amendment 81K proposes setting up a parliamentary commission between the United Kingdom and Mauritius. The proposal is that we seek to agree with Mauritius that this parliamentary commission should reflect equal representation from the Parliaments of the United Kingdom—this Parliament—and the Republic of Mauritius, which one hopes would be acceptable to the Mauritians as fairly rational in these circumstances. More important, what is the function of this commission? It should be to ensure,

“the recognition and protection of Chagossian rights, including but not limited to … ensuring a right of return … ensuring the right to self-determination via a referendum of all Chagossians on the question of sovereignty is held by the UK”,

and

“access to compensation, resettlement, or other forms of support”.

The Minister has repeated again today this extraordinary affirmation that there is no Chagossian people and never has been—that there has never been any permanent population of the Chagos Islands. I can see why the Minister can say that there no longer is, because we shamefully removed them. But to rely on the fact that we removed them and therefore they are not permanent, when all of us now think it was monstrous that this was done with no possibility of return at the time, and that we should be setting this right, now that we are trying to sort the aftermath of decolonisation, as it is seen, is to my mind extraordinary. How can there have been no permanent population in the past if there are churches, graveyards, signs of habitation, work, agriculture and fishing on several of the islands? Above all, how can we pretend that there never has been any Chagossian population and, at the same time, grant British citizenship to those who can demonstrate that they are descended from Chagossians?

The Minister cannot have it both ways. She cannot say that there has never been anyone there and that we are now recognising that those who have been there, or are descended from them, have the right to British citizenship. It is there in the treaty. I know that when she mentioned this she said it with obvious distaste and embarrassment, but that distaste and embarrassment should have been sorted out with her officials before she got round to saying it again in this Chamber. It is very insulting to the Chagossian people to say that they have never existed.

Given that the Chagossian people have existed, and that we recognise that it was wrong to remove them without in any way trying to provide them with some prospect of undoing that wrong, surely we should, through the parliamentary commission that I propose in this amendment, discuss with the Mauritians, if sovereignty is handed over to them, at least giving Chagossians the right of return and the right of self-determination via a referendum, along with access to compensation, resettlement or other forms of support. If we do that then at least we will go a small way to undoing the wrong that was done in the late 1960s—I think it extended into the 1970s—which all of us now recognise.

It is clearly important that we have some kind of parliamentary commission overseeing this, because the treaty does not do these things. It could allow the resettlement to be extended to Mauritians and not be given to Chagossians, and it could result in the fund that we set up not being paid out to Chagossians—certainly not to Chagossians who have been in the United Kingdom, but solely to Chagossians who now live in Mauritius. It is only right and proper that we have some parliamentary oversight from both sides—from Mauritius as well as from the UK—to ensure this is all properly done. I am sure this proposition is so reasonable that such a reasonable Minister as we have on the Front Bench cannot fail to agree with it. I beg to move.

[The Earl of Leicester (Con)]

I want to add to my noble friend’s words. I will not read the whole letter, but this is a copy of the letter to the Minister from the Chagossian people. They write that the Minister’s words

“cut deeply. They erase our history, our dignity, and the truth of who we are. They echo the very language used to justify our people’s deportation between 1968 and 1973. And they are demonstrably false … For more than a century before our exile, the Chagos Islands were home to a multigenerational, settled population. This is not our opinion. It is documented in church registers of births, marriages, and burials across Peros Banhos, Salomon and Diego Garcia; colonial-era records describing communities with homes, chapels, gardens and workplaces; judgments of the UK High Court in the Bancoult cases; the International Court of Justice; United Nations resolutions; academic research stretching across decades. We were not transient workers. We were a Creole-speaking people, rooted in our islands, with our own traditions, our own culture, and our own community life. To say that our homeland had ‘no permanent population’ is simply untrue … You also stated the islands had ‘never been self-governing’. Chagossians have never claimed to have operated a Westminster-style system. But for generations, in the long absence of resident British administrators, our islands were organised and cared for by local leaders from within our own community”.

This has been confirmed in academic work. Misley Mandarin, who lives here in London now with his family, finishes,

“We ask you not for sympathy, but for recognition. Not for pity, but for accuracy. Not for charity, but for truth. We deserve self-determination. We want to stay British and return to our islands as British citizens”.

[Lord Callanan (Con)]

My Lords, Amendments 20T and 81K, in the name of my noble friend Lord Lilley, seek to achieve a similar objective to Amendments 80 and 82. Given the similarity of the two pairs of amendments, I was slightly surprised to see the noble Lord, Lord Purvis of Tweed, degroup his amendments. We could have had a very satisfactory debate with the original grouping, but of course I fully respect the noble Lord’s right to degroup his amendments. I am slightly surprised, because he criticised me for doing something similar last week, but it is, of course, only right that noble Lords should be able to debate their amendments in the groupings that most suit them.

I am pleased that my noble friend Lord Lilley has the right to self-determination, as confirmed by a referendum of the Chagossians, in his amendment. This is an important point that I am sure many noble Lords will agree with.

Amendment 20T would also delay the implementation of the key parts of this Bill until some progress has been made on establishing the joint parliamentary commission. It seems to me that too many core parts of the treaty are not tied to deadlines or quantifiable outcomes. As a result, it would be hard to monitor whether Mauritius, and indeed the UK, are fulfilling their obligations under the treaty in a timely manner. My noble friend Lord Lilley’s amendment helpfully ties the joint parliamentary commission to the coming into effect of the Act, forcing Ministers and their Mauritian counterparts to get on with the job so that the commission can play an important role from the very beginning of the treaty’s effect. It is a very sensible proposal.

I look forward to hearing the Minister’s response on whether the Government will agree that establishing a joint parliamentary commission would be a useful tool going forward.

--- Later in debate ---

[The Earl of Leicester (Con)]

My Lords, in this amendment, we are talking about a democratic study of the Chagossian people. However, I want to speak about a matter that has been mentioned briefly by my noble friend Lord Callanan and that goes to the very heart of democratic integrity and the dignity of an entire people.

I wish to address a survey issued by the House of Lords International Relations and Defence Committee that aims to capture

“Chagossian views on the Agreement with Mauritius concerning the Chagos Archipelago”.

This survey cannot be relied on. It is methodologically flawed, structurally careless, open to manipulation and in several aspects dangerously misleading. The Chagossian people, who have endured decades of dispossession, displacement and injustice, deserve far better than an instrument that falls short at every level.

First, on the technical design, the survey is hosted on Microsoft Forms, a rudimentary platform that any undergraduate research supervisor would reject for a project involving even minimal verification. There are no safeguards against duplicate submissions, no protection against cyber manipulation, no identity checks and no mechanism whatever to confirm whether a respondent is actually Chagossian. For a survey that concerns sovereignty, citizenship, resettlement and the legacy of one of the gravest forced removals in modern British history, this is astonishing. It leaves the process exposed to interference by anyone, anywhere, with any motive.

Unfortunately, that is not a theoretical risk. The survey still has a week to run, and we already have deeply troubling reports from Mauritius. There are claims, supported by video evidence which I have seen and direct testimonials, that Mauritian officials and intermediaries have been filling out the survey on behalf of Chagossians who cannot read English, cannot understand the political implications and cannot write their own responses.

Even more seriously, multiple Chagossians have told us that they oppose the agreement with Mauritius yet believe that they have been marked down as supporting it in this survey. If this is true, then a foreign Government are, in effect, interfering with a House of Lords committee’s evidence-gathering process. Not only does this compromise the validity of the survey but it threatens the independence and integrity of Parliament itself. Let us be absolutely clear: this is not a consultation but contamination.

Let me take your Lordships through some of the survey questions. It begins with text that states that:

“A new law implementing the Agreement is currently being debated … and members of the House of Lords want to hear … opinions … before voting on it”.


What it does not say—and very much ought to—is that this agreement is not yet in force, that ratification is required and that Parliament can still reject it. The omission is misleading and may lead many to believe the treaty is inevitable. When you are asking a displaced people about the fate of their homeland, clarity is not optional; it is essential.

The survey repeatedly instructs respondents not to provide any identifying information. At the same time, it allows anyone in the world to submit answers as many times as they like, with no checks. There is no way to confirm whether responses come from Chagossians, non-Chagossians, organised political activists or even automated submissions. I have personally seen a text message from a high-ranking Mauritius official stating:

“My guys in the Mauritian Government are”—


I will change the wording—very worried.

“They are planning for civil unrest when they cancel the tax cuts”.

It is clear what the Mauritians want. For a consultation that claims to express Chagossian views, this alone renders the entire exercise invalid.