Diego Garcia Military Base and British Indian Ocean Territory Bill

Lord Browne of Ladyton Excerpts

Tuesday 4th November 2025 Lords Chamber

[Lord Browne of Ladyton (Lab)]

My Lords, I am pleased to follow the noble Baroness, Lady Meyer—despite not agreeing with a word she said. I am pleased because I have waited a long time to make this relatively short speech in this debate.

I concluded my contribution to the debate on 30 June on the Motion from the noble Lord, Lord Callanan, with the following sentence:

“I will offer this agreement my full support in these and any other proceedings in your Lordships’ House”.—[Official Report, 30/6/25; col. 524.]


That is still my position in relation to both the agreement and the Bill, the more so because, as my noble friend Lady Liddell remarked in the earlier debate in June, and as the noble Lord, Lord Jay of Ewelme, reminded us today:

“Our allies, not just the Five Eyes communities of the US, Australia, Canada and New Zealand—along with ourselves—but India, Japan and South Korea—


and the African Union

“—strongly support the deal”.—[Official Report, 30/6/25; col. 501.]

I congratulate my noble friend Lady Chapman of Darlington on her comprehensive opening remarks. I thank her and my noble friend Lord Coaker for their openness and engagement with noble Lords on the many issues and complications that are raised by this treaty. I thank my noble friends in particular for arranging an all-Peers drop-in session on the Bill on 29 October, and even more for ensuring that the key FCDO officials, including the UK chief negotiator, Harriet Matthews, were present to share their knowledge and respond to noble Lords’ remarks or questions, which they did candidly and, in my view, credibly. I am only sorry that the representatives of the Official Opposition who were in the room at the beginning of that conversation mostly left without taking advantage of the opportunity to question those who negotiated this and to ask the questions that they clearly have.

In as few minutes as I can possibly do, I will focus my speech on what was the main purpose of my speech on 30 June: to examine, in so far as I am able to, the principles that appear to underlie opposition to this treaty and, consequently, to the Bill.

The strategic importance of Diego Garcia and its base to the United Kingdom and the United States, and to all our allies globally, is well known. Interestingly, I found in my research, despite the fact that much of the commentary about this base refers to it as a secret base, that it is very easy to find out the detail of quite a substantial amount of its capability in open source. It is available in some detail. I proceed on the basis that no one engaged in this debate needs to be reminded of the specific or strategical operational support that it offers. My own experience of its importance to UK security and to that of our allies was the support that it gave our operations both in Iraq and in Afghanistan when I was the Secretary of State for Defence. I have no intention of going into the detail of that, but it is well known and, for those who do not know, a lot of this can be found in open source.

As a consequence of our agreement with Mauritius, we will have access to this capability, enhanced by more investment by the United States. It is not a case of saying that if we pay, the United States stays. The United States invests many multiples of its cash in this base in order to give it the extraordinary capability that it has. Nobody can do anything to change its position on the global map, but the Americans can continue to invest for a period and they have plans to invest further in the long term. We will get value for our money from what the Americans do to help support us and the way in which we work with them to make sure that capability improves all the time.

However, the fact of the matter is that in 2019, when the International Court of Justice issued an advisory opinion concluding that the UK’s administration of the Chagos Archipelago was unlawful and that Mauritius has sovereignty over the territory, it immediately imperilled continuing new and planned investment in Diego Garcia. I worry if this is not known to those on the opposite Benches. I understand, from an open source comment, that the US suspended that investment until the issue of sovereignty had been resolved. One of the advantages of having the negotiators in the meeting of 29 October was that I was able to ask them openly if the information, which is available for people to see and read, was known to the FCDO: was the fact this link existed known to the Government at the time when the negotiations started?

The uncertainty that justified the United States position is to be found in the evidence given by Sir Christopher Greenwood to the International Agreements Committee, which has also been referred to earlier by other speakers. Sir Christopher Greenwood is one of the UK’s pre-eminent practitioners of international law and a former judge in the International Court of Justice. In his opinion, any international court examining the sovereignty dispute would likely find in favour of Mauritius. Such an outcome would clearly represent a risk to the future of the military base, and thus to the UK’s national interests and security. That is not something we can just dismiss. Had the issue of sovereignty not being resolved by a negotiation, the suspension of US investment would also have represented a risk to the future of the military base, and thus to the UK’s national interests and security. That is the environment in which these decisions to enter negotiations were made back in November 2022.

I practised law for the best part of 20 years before I was elected. A substantial proportion of my practice was in negotiation. There are many lawyers in this House and I am sure that they realise that lawyers spend more time in negotiation than in almost anything else. On some occasions, my clients wanted me to enter negotiations in order to protect a status quo— I think we have called that a red line in this debate. It appears to me, from the many speeches that I have listened to, that this was the latter objective of the negotiations that the Conservative Government started: to get back to the status quo.

I always told my clients that I would argue for the status quo in negotiation but, if there was a judicial assessment that made the status quo unattainable, it would be a failure in the negotiations to try to achieve that. That is the situation that the Government were in in 2022.

The whole process, of course, started with the Written Statement made on 3 November. There has been toing and froing about what was said in the Statement in order to try to water it down, but let me read the first paragraph of that Statement, because it is extraordinarily revealing as to what the then Government were seeking to do. It reads:

“Following the meeting between the then Prime Minister, my right hon. Friend the Member for South West Norfolk … and Prime Minister Jugnauth at the UN General Assembly, the UK and Mauritius have decided to begin negotiations on the exercise of sovereignty over the British Indian Ocean Territory (BIOT)/Chagos archipelago”.


Next comes the important sentence:

“Through negotiations, taking into account relevant legal proceedings, it is our intention to secure an agreement on the basis of international law to resolve all outstanding issues”?—[Official Report, Commons, 3/11/22; col. 27WS.]


In other words, we were beginning to negotiate with the only people we could negotiate with—Mauritius, which was holding this particular card—to transfer the sovereignty to them in a way that would give stability, allow our major ally to get back into the relationship that we had, and continue to build this mother of all bases in the world. It is as simple as that.

I do not understand why everyone is looking for explanations for this by suggesting that, in these 11 exercises of negotiation, we were seeking to do something else. It is perfectly clear what the Conservative Government was setting out to do. They were pushed into this position by the fact that the United States was unwilling to continue to invest in this until that uncertainty was resolved.

On 29 October, I took the opportunity to ask the negotiators if that was what they understood to be happening; that is exactly what they understood to be happening. I understand why now, for political reasons, the Opposition wish to rewrite this, but that is what they were doing and what we continued.

Secondly—

[Noble Lords]

Oh!

[Lord Browne of Ladyton (Lab)]

I am happy to stop there because I have made my point. The nonsense about the Chinese has already been dealt with.