Diego Garcia Military Base and British Indian Ocean Territory Bill

Lord Purvis of Tweed Excerpts

2nd reading
Tuesday 4th November 2025 Lords Chamber

[Lord Callanan (Con)]

I am happy to tell the Minister that I have spoken to the noble Lord, Lord Cameron, about that. He agreed that it was paused, which I think she has just confirmed.

Alas, Ministers no longer have the clarity of mind needed to deliver for the British people and, as so often with this Government, they have allowed themselves to be taken in by their international lawyer friends and donors. This all begs the question: why? Why did Ministers feel the need to pursue this agreement that puts Britain’s interests last? Why have the Government seen fit to saddle taxpayers with an additional financial burden, at a time when we are all being softened up for massive tax rises from the Chancellor of the Exchequer?

Ministers have told us, as the noble Baroness did again today, that this agreement is a legal necessity, but, as we heard from my noble friend Lord Wolfson of Tredegar when we debated the Motion to approve the treaty—I commend his speech to noble Lords who have not had the chance to see it yet—there is a range of views among very senior lawyers on this matter. The Government cannot hide behind legal advice, unless they want to publish it for us all to see. This was a political decision for which Ministers must take the political responsibility.

The almost single-minded obsession with international law has blinded the Government to the real threat from a country that itself pays absolutely no heed whatever to that same international law. We know that China has said that it wants to deepen its strategic partnership with Mauritius. As recently as 15 May this year, China’s ambassador to Mauritius said that the People’s Republic of China wanted to strengthen ties with Mauritius, noting the country’s “strategic advantages”, and expressed a commitment to elevating the bilateral strategic partnership. The Chinese ambassador to Mauritius is on the record as offering, unsurprisingly, massive congratulations on the deal and stating that China fully supports Mauritius’s attempt to “safeguard national sovereignty”. It is a shame that China does not show that same regard to the national sovereignty of other nations.

That is who the Government have appeased with this agreement. When the Government took office, they claimed that they would protect our national security. Can the Minister please explain how ceding national sovereignty to a country that is known to be deepening its ties with a nation that we know to be a threat to the UK will help them achieve that manifesto commitment?

As the Official Opposition, we will seek to amend the Bill in your Lordships’ House to ensure that the Chagossian community is properly consulted and that the agreement facilitated by the Bill does not put the desires of international lawyers before the interests of the British people, who have paid the taxes which are now to be transferred with careless abandon to Mauritius.

Speaking of the rights of the Chagossians, I find myself on this occasion in the unusual position of agreeing with noble Lords to my left when I say that the Government have not handled this well. In the other place, the Liberal Democrat spokesman, Dr Al Pinkerton, said that,

“this Bill fails the Chagossian people”.—[Official Report, Commons, 20/10/25; col. 756.].”

On this, we agree. Ministers have failed to properly consult the Chagossians to the point that the community is now furious with this Government, as we have all seen from our email inboxes.

However, there was another way. In the other place, the shadow Foreign Secretary, Dame Priti Patel, tabled a presentation Bill which included specific requirements

“to consult and engage with British Chagossians in relation to any proposed changes to the sovereignty and constitutional arrangements of the British Indian Ocean Territory”.

That is what should happen. The Chagossian community should be heard and not ignored.

In conclusion, the questions at the core of all our debates will remain these. Is this treaty a good deal for Britain? Does the Bill put us in the service of the British people? I do not think that it does—

[Lord Purvis of Tweed (LD)]

My Lords—

[Lord Callanan (Con)]

We will set out our reasons in detail, if the Bill ever returns to your Lordships’ House. I give way to the noble Lord.

[Lord Purvis of Tweed (LD)]

I have listened carefully to all the noble Lord’s contributions. I fear that he has missed something out, and I want to help him. First, can he explain briefly whether international law advice which was given to the previous Administration over the status of British sovereignty, and which has not changed for this Administration, has changed? Secondly, why did James Cleverly, on 3 November 2022, make a Statement to Parliament that that Government had decided to begin negotiations on the exercise of sovereignty over the BIOT Chagos Archipelago? If everything that he said was a point of principle, why did the previous Government accept that negotiations had to start on ceding sovereignty?

[Lord Callanan (Con)]

I am always suspicious when the Liberal Democrats say that they want to be helpful. We have debated all these points at length.

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[Lord Lilley (Con)]

My Lords, it is a great privilege to follow the powerful speech by my noble friend Lady Foster of Aghadrumsee. I am tempted just to say “ditto” and sit down, but that is not the practice in this place, so I will focus on some aspects that differ from the focus that she gave. The importance she attached to the Chagossians enables me to be a bit briefer than I would otherwise have been.

I want to return to a powerful assertion that was made the first time this House considered a Statement on this subject, which was diluted a bit today in the defence put forward by the noble Minister. The original Statement by the Defence Secretary said

“without this deal—within weeks we could face losing legal rulings, and within just a few years the base would become inoperable”.—[Official Report, Commons, 22/5/25; col. 1284.]

What is the likelihood of us facing a legally binding ruling? If so, I ask the Minister, from which court is it likely to come?

First, as even the Foreign Office recognises, the opinion of the International Court of Justice was purely advisory, not binding. Secondly, it was based on UN General Assembly resolutions. Such resolutions are not legally binding, especially as they have not been endorsed by the Security Council. Thirdly, when the UK signed up to the International Court of Justice, our declaration specifically said that the Government of the UK excluded the jurisdiction of the International Court of Justice on

“any dispute with the government of any other country which is or has been a Member of the Commonwealth”,

as is Mauritius. Hence, the opinion of the ICJ was triply non-binding, and no future ruling of the ICJ on this dispute could be binding on us.

Ministers never mention these facts; either they are unaware of them, or they do not want us to know. Instead, they segue on to discussing the UN Convention on the Law of the Sea, as the noble Baroness did today, since that also has a tribunal. However, Article 298 of that treaty provides that states may “at any time” exclude “disputes concerning military activities”. Therefore, it is hard to see how the UNCLOS tribunal could reach a binding ruling which would impede our use of the base, still less do so in ways that the Defence Minister originally spelled out when he said:

“Rulings against us would mean we could not prevent hostile nations from setting up installations … on the outer islands … we could not guarantee the safe berth of our subs, patrol the waters around the base, control the airspace directly above or protect the integrity of our communications systems”.—[Official Report, Commons, 22/5/25; col. 1284.]


All that seems impossible to come from a tribunal which excludes, or where we can exclude, military matters.

These are not the only issues which the Government refuse to address. They never mention—even the Explanatory Memorandum on the agreement ignores it—the Pelindaba treaty, to which Mauritius is a signatory. It is signed by all countries counted as in the African region—and Mauritius is one—making Africa a nuclear-free zone. The treaty allows no reservations, at the time or subsequently, so it will apply to Diego Garcia, and it cannot be overridden by our treaty unless Mauritius resiles from the Pelindaba treaty. Do the Americans accept that that will mean that no nuclear weapons-carrying vessels or planes can use the base?

The agreement with Mauritius purportedly relates to completing the decolonisation of Mauritius. There are two relevant principles that have a bearing on the process of decolonisation. The first is the right to self-determination, and the second is the principle of territorial integrity. This agreement elevates the principle of territorial integrity above that of the right to self-determination.

It is bizarre that boundaries laid, and former administrative arrangements imposed on an area, by the colonial power should be treated as so sacrosanct, whereas the rights of the people who were displaced—many of whom would like to return or have the right to return—are to be ignored. It is even more bizarre given, as my noble friend Lord Callanan pointed out, the promise in the Labour Party manifesto that it would support the sovereignty, integrity and right to self-determination of peoples in the British Overseas Territories. I wait in the summing up to hear how the Government reconcile their promise made to the British people, and to the peoples of those territories, with what they are doing today.

Why are the Government ploughing ahead? Of course, they refer to the fact that negotiations began under the previous Government, although they were paused by the noble Lord, Lord Cameron. At the time they were paused, I found myself discussing this with a Foreign Office official, who I heard mention the agreement. I said, “Isn’t it good that these negotiations have been paused?” He obviously did not approve of the negotiations. He said, “Oh, it’ll make no difference; they’ll continue. It is the settled policy of the Foreign Office, whichever Government are in power, that we shall continue with this process to give away the sovereignty of them”.

[Lord Purvis of Tweed (LD)]

All the legal considerations that the noble Lord has outlined to the House, including those in the latter part of his remarks, pre-date November 2022, when the previous Government started negotiations to cede sovereignty. They took all his remarks into consideration, so why did they start negotiations to cede sovereignty?

[Lord Lilley (Con)]

The noble Lord is making a party-political point, as the Lib Dems always do. I am accepting that both parties are allowing themselves to be driven by the settled policy of the Foreign Office. We have to recognise that.

[Lord Purvis of Tweed (LD)]

It started in 2022.

[Lord Lilley (Con)]

Whenever it started, the settled policy of the Foreign Office will probably continue for another 22 years. Anyone who has been a Minister knows that every department has a settled policy that continues unless Ministers come along and determine to overthrow it.

[Lord Purvis of Tweed (LD)]

Earlier in 2022, the then Government’s view was that there would be no change to the sovereignty of Chagos. That was a Statement given to Parliament in early 2022. The policy changed under Liz Truss as Prime Minister and James Cleverly as Foreign Secretary to start negotiations to cede sovereignty. If there had been a settled will, it had been the one before the Government changed policy. It was the noble Lord’s Government who changed the policy.

[Lord Lilley (Con)]

Of course it was, but they allowed it to be changed from pressure from the Foreign Office. We can go into the archaeology of when this surfaced in the form of government policy and when it was internal, but I have no doubt that it was. Whenever I have spoken to Foreign Office officials, they have acknowledged that we are not bound by rulings of the court, nor are we likely to be, and nor are we bound by the obligations of any treaty, but they argue that Britain must none the less abide by even non-binding advisory opinions, since if we do not, how can we tell other countries that they must abide by international law? That is precisely the argument that was forwarded just now by the noble Lord, Lord Hannay.

It is touching that our diplomats believe that countries that might otherwise flout international obligations and rulings will change their ways and become law-abiding if they see us obeying rulings that we do not have to abide by and being purer than pure. I believe that the policy of the Foreign Office, and, above all, the policy of elected officials in charge of the Foreign Office, should be to pursue British interests and not to set about setting examples to other countries and virtue signalling. That is what this is doing, and it is weak for that reason. I hope that the House will in the weeks to come persuade the Government to abandon it.

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[Lord Purvis of Tweed (LD)]

I would prefer the noble Baroness to be consistent. If she is criticising the Attorney-General under this Government for giving advice on continuing negotiations to cede sovereignty, why is she not as critical of the noble and learned Baroness, Lady Prentis, who was Attorney-General in November 2022, when, presumably, she gave advice to the previous Government to commence negotiations to seek sovereignty?

[Baroness Hoey (Non-Afl)]

The noble Lord has obviously seen some of these legal agreements. I have not. I would like to see all this legal advice. I see no reason why this House should not see the legal advice.

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[Lord Murray of Blidworth (Con)]

As I said earlier in my remarks, that was a decision with which I strongly disagreed then, and I strongly disagree now. He was plainly wrong in so saying.

[Lord Purvis of Tweed (LD)]

My Lords—

[Lord Murray of Blidworth (Con)]

Forgive me: I have given way once, and time is limited.

Professor Ekins, professor of law and constitutional government at Oxford, set out in detail, when he gave evidence to the House of Lords International Agreements Committee, the failings in the treaty. In particular, he set it out in even more detail in his Policy Exchange paper published at that time. I strongly urge the Minister to consider those two items in detail during the pause in proceedings brought about by the decision not to proceed with the committal Motion tonight.

There can be little doubt, contrary to the Government’s expostulations about saving the base, so ably outlined by my noble friend Lord Altringham, that this in fact weakens the strategic interests of our country. It does so without any sound legal or geopolitical basis, and, as many noble Lords have noted, without any reference to the wishes of those who lived in the archipelago, shamefully removed on the orders of a Labour Government —a shame that, as the noble Lord, Lord Morrow, noted, is about to be repeated and amplified by this present Labour Government.

Finally, the Minister said that the previous Government had entirely overlooked the Chagossian people, a calumny that was repeated by the noble Lord, Lord Beamish. Not so. Section 3 of the Nationality and Borders Act 2022 —a Conservative piece of legislation—was the first legislation to make provision for Chagos Islanders and their direct descendants to obtain British nationality, something successive Labour Governments had failed to provide.

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[Lord Purvis of Tweed (LD)]

My Lords, I wish to acknowledge those of the Chagossian community who are here observing this debate, those following it at home and those who will read it. My noble friend Lady Ludford, in her powerful contribution to the debate, informed by decades of work on behalf of the Chagossians, told us of the remarkable sequence of November anniversaries, including some which are a dark stain on this country with regards to how we have treated the Chagossian community. We should all share blame for this generational mistreatment.

I start by stressing in clear terms that we still need more clarity on the rights given, potentially, to the Chagossians of a permissive nature, but by virtue of us providing those rights to the Mauritian Government, not directly to the Chagossians themselves. I hope the House will recognise that this has been a consistent and constant concern of these Benches, and it continues. We pursued it in the debate on the treaty and I am glad that the Minister acknowledged it in her opening remarks. My colleagues in the House of Commons pursued it when the Bill was in Committee there and I reiterate it today.

A test for us now is how, finally, we give rights back to Chagossians, including the right of self-determination for their future, which should be in their hands. If we negotiate an agreement on Gibraltar with the statement, “Nothing for Gibraltar without the Gibraltarians”, that should apply in this context too. Indeed, we divided the House of Commons in Committee on the right to self-determination. It is worth placing on the record in this debate, which I point out to the noble Baronesses, Lady Foster and Lady Meyer, that the Conservative Official Opposition did not support us in that. It is fine to call for self-determination and a referendum in this debate, but it is worth recalling that, just a couple of weeks ago, that party opposed it in the House of Commons.

We touched a little on history today. I went through a lot of the history in the debate on the treaty, so I do not need to rehearse it. Today, there was a slight new edge to this. It was interesting that the noble Baroness, Lady Noakes, and the noble Lord, Lord Hannan, criticised the Labour Government for concluding an agreement in 1965. That may well have had cross-party support, but the noble Lord, Lord Murray of Blidworth, called it a shame on our country. With interesting parallels, it should be recognised that negotiations to detach the Chagos Archipelago from Mauritius commenced on 29 June 1964, under the Conservative Government. The Conservative Party has form, as the noble Baroness, Lady Noakes, might say.

[Lord Murray of Blidworth (Con)]

Forgive me, but the shame, as I am sure the noble Lord will agree, comes from the removal of the Chagossian people from the Chagos Islands, not from the agreement itself.

[Lord Purvis of Tweed (LD)]

Yes, and as the noble Lord will recall from the debate that we had on the treaty, that was accelerated under the Heath Administration in 1970 and concluded under the Conservative Government. The denial of repatriation was then subsequently under another Conservative Government. My point is that all of us in this country have a dark record when it comes to Chagossian rights. Our task now should be how we at least restore some of those.

The noble Lord, Lord Callanan, started his remarks by saying that the House of Commons was denied the opportunity of debating the treaty during the Constitutional Reform and Governance Act period of scrutiny. He knows, because he will remember the debate we had on the treaty, that, as Erskine May makes perfectly clear, one of the mechanisms for the House of Commons to deny ratification of a treaty would be through an Opposition day debate. During the scrutiny period of this treaty in the House of Commons, the Conservative Party chose a different subject for its Opposition day debate. It had the chance, if it chose to take it, of debating and moving an amendment in the House of Commons during the scrutiny period.

We are here today debating this Bill for one reason and one reason alone: the previous Administration made a political decision to cede sovereignty and to enter into negotiations to conclude this. I hear noble Lords saying no, and I will come on to that, when they may wish to change their minds. Not one Conservative colleague today said why the previous Government opened negotiations to cede sovereignty in 2022. The then Government did not open negotiations to improve relations or co-operation with Mauritius. They made the principal decision to cede sovereignty, but they still have not said why. I hope the noble Baroness, Lady Goldie, will outline clearly today why that was the case.

All legal considerations on this issue, which have been debated quite a lot during this debate, predate 2022. The complaints received in this debate predate James Cleverly and that Government’s decision. We have had complaints in this debate from the noble Baroness, Lady Hoey, of the current Attorney-General and the advice given to this Administration. As my intervention on the noble Baroness suggested, the same would have been the case under the previous Government. I assume that when the previous Government made the policy decision in November 2022 to open negotiations which would conclude with the ceding of sovereignty, they were also advised by Attorneys-General. I have a hunch that it might have been the Attorney-General at the time of November 2022, but it could have been any of the three Attorneys-General that the Government had in 2022. No doubt, history will tell us which one of those it was.

A new argument has been presented today by the noble Lords, Lord Lilley and Lord Blencathra, that the Conservative Government were powerless and feeble and that their Prime Ministers and Foreign Secretaries were forced against their will by officialdom to make that statement in 2022. This is the argument of being in office but not in power. It was our suspicion at the time that the Conservatives were in office but not in power, and I am glad noble Lords have confirmed that.

I understand the argument that might say that this is a bad deal or that it has been handled badly. I think that many parts of it remain problematic, and I would have liked the Government to have handled it differently. But that is different from the Conservative Opposition in the Commons, who said in their amendment that they were “implacably” opposed to “ceding sovereignty”. They were not implacably opposed to ceding sovereignty in November 2022, so what changed?

[Lord Bellingham (Con)]

The noble Lord is actually putting a very strong case. What I said in my speech was that there was a red line about a sovereign base area—the concession of sovereignty across all the rest of the territory, but keeping the sovereignty of the base.

[Lord Purvis of Tweed (LD)]

I am grateful to the noble Lord; I listened carefully to his speech, which he made in his characteristically sincere way. I will try to address that point in a moment.

I asked: what changed? In the absence of the noble Baroness, Lady Goldie, explaining when she winds up on behalf of her party what policy changes were being made, I might assume that the only relevant change is the fact that the Conservatives were in government and are now in opposition. Without there being a clear policy change, we can only make that assumption.

This is quite important because the Statement in 2022 said,

“on the exercise of sovereignty”.—[Official Report, Commons, 3/11/22; col. 27WS.]

I have wondered why the same party that was implacably opposed then can be in favour of it now, especially because that Statement by the Government said that they were doing this to “resolve all outstanding issues” of international law. They knew that they had to resolve those outstanding issues of international law, but now they are denying the very virtue of the fact that they had any issues at all to address. That is quite hard to understand, and they have not made it any clearer today.

The point made by the noble Lord, Lord Bellingham, was also made by the noble Lord, Lord Blencathra. The 2022 Statement, which was the policy choice of the previous Government, was a mistake—as the noble Lord, Lord Bellingham, indicated; I respect his honesty —or was, according to some of his colleagues, the result of deep state. Nevertheless, if that had raised serious defence concerns, the Minister of State in the Ministry of Defence at the time would presumably have raised concerns about it. That Minister was the noble Baroness, Lady Goldie, so she has ample opportunity to address the noble Lords’ points in her speech today.

[Baroness Hoey (Non-Afl)]

We have heard a lot about what has gone on in the past and whether the Conservatives did this or that. What I want to know is: are the Liberal Democrats implacably opposed to this treaty? Do they want to see the Chagossians be given full democracy and have their rights listened to?

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[Lord Purvis of Tweed (LD)]

I am sure that the noble Baroness heard me—I am sure she was paying attention to the early part of my contribution—when I said that we moved that very Motion in the House of Commons just a few days ago but did not get support from the Official Opposition. So I appeal to the noble Baroness to wait until the noble Baroness, Lady Goldie, makes her contribution and then to intervene on her with the same question.

The noble Lord, Lord Murray, made an interesting contribution. It was a post hoc breach of collective responsibility when he referred to his letter of opposition to that policy choice of his Government. I was going to intervene on him to ask politely whether he would place that letter in the Library for us all to see; I am very curious about it. I would be interested to know how many of his colleagues made the same complaints. I have mentioned the fact that one of those colleagues was the noble Baroness, Lady Goldie; of course, another of his ministerial colleagues at the time was the noble Lord, Lord Callanan. He did not intervene on the noble Lord, Lord Murray, so I assume that he did not write a letter of complaint at the time; I am sure that we will find out in due course.

Ultimately, we have to recognise, to be fair to the previous Government, that they entered into negotiations in good faith. I do not think a British Government would likely enter into negotiations on the ceding of sovereignty if they knew that the conclusion of that was not the ceding of sovereignty, so I give credit to the previous Government for acting in good faith about that. The question now is how we seek to raise our concerns on those very aspects of the Chagossians’ right to self-determination and on the scrutiny and operation of the trust fund. I hope we can continue to raise these concerns during the passage of the Bill in good faith.