Diego Garcia Military Base and British Indian Ocean Territory Bill

Lord Houghton of Richmond Excerpts

Report stage
Monday 5th January 2026 Lords Chamber

[Lord Craig of Radley (CB)]

My Lords, happy new year to everyone. I will speak to Amendments 1 and 38. In an earlier debate on the Bill, I raised the concern that the UK is required, under Article 11 of the treaty, to continue to pay Mauritius even were the military base on Diego Garcia to become unusable. There seems to be no break or conditional clause agreeing any reasons why the UK may cease these payments before the 99-year date is reached.

Article 15 sets out how Mauritius may react should the UK cease payment, but this is a reason why Mauritius may terminate the treaty, not the UK. If the UK were to persist in not honouring its obligation to pay, the treaty would perforce be terminated by Mauritius. For the avoidance of doubt, would that mean that Article 1 of the treaty is still applicable and sovereignty would remain with Mauritius? Can the Minister confirm the Government’s view on this? I have forewarned her of this question.

In Committee on 18 November, the Minister said in response to my question about the base no longer being usable:

“I will reflect on this and try to come back to him with a more thorough response, because I can see that he … wants to know that the Government have given this the proper consideration that he would expect. I undertake to do that”.—[Official Report, 18/11/25; col. 772.]

If she has written with this further information, I have not yet received it. Fundamentally, does she feel that the environmental risks and the risks of other possible events, such as a major destructive attack on the base or even a decision by the United States that it has no further use for it, are sufficiently remote and unlikely for the UK to be able to accept—or have a possibly messy and even dishonourable termination, where considerable sums of taxpayers’ money may be involved?

As this is Report, I do not intend to do more than point this out without detail, but experience tells us that much can and does change over time. In well under the past 100 years, foes have become friends and friends, potential and real, have become foes. Weapon technology may well change and has frequently done so, as has how operations are mounted and security maintained. America could decide that it has no need for the base for operational reasons or even cease to act as a world police force and revert to isolationism. Is there any legally binding agreement between the UK and the United States that it will continue its use of the base or have need of its use for the 99-year duration of the treaty?

I do not wish to suggest any lack of importance of the base to national and international security at the present time. There is also the putative threat of the sea rising this century due to global warming, flooding the base. My Amendment 1 suggests one feasible way to correct this apparent lack of foresight. I shall listen with close interest to the Minister’s response, but unless the Government can reassure the House that the issue of non-usability of the base has been fully considered and a reasonable solution adopted, I may seek the views of the House. I beg to move.

[Lord Houghton of Richmond (CB)]

My Lords, I rise to speak in support of Amendment 1, to which I attach my name, and to reinforce the arguments made by my noble and gallant friend Lord Craig of Radley. This amendment is not moved by any wider purpose than common sense, and we trust that the Government will respond accordingly.

Currently, the Bill makes no provision for the circumstances under which the requirement to pay an annual fee for the use of the Diego Garcia base is revisited in the event of the base becoming unusable for military purposes. My noble and gallant friend has already mentioned the potential risks to the utility of the base arising from an extreme environmental event, the future potential for a policy change by the United States and the potential for the technical obsolescence of the base to come about. I argue that concerns regarding potential legal initiatives to constrain the use of the base, particularly partial constraints deriving from nuclear exclusion agreements or the question of Mauritius as the sovereign power having to honour obligations for the authorisation of offensive operations from the base, should be added to that list of concerns.

I fear that the greatest future concern should perhaps be the full or partial destruction of the base through military action by a hostile state. This might seem a surprising concern given the extremely remote nature of this base, but I have been to it. I argue quite strongly that the strategic importance of the base, its entirely militaristic purpose and its extreme remoteness from civilian life all combine to make it a highly vulnerable and attractive target.

The principal tenets for the use of force in warfare are distinction, military necessity, humanity and proportionality. Pause for a moment to imagine the early stages of a global conflict, when a desire for escalation dominance prompts a hostile nation to destroy a western strategic asset as a proportionate response, with no risk of collateral damage to a civilian population, attracting relatively minor moral opprobrium but resulting in huge military benefit. I cannot think of an obviously better or more considered target than Diego Garcia.

Many in the Chamber may think my concerns are drawn from the world of fantasy or nightmare, but do the last 72 hours not give serious cause for concern regarding our ability to predict with certainty the next two years of geopolitics, let alone the next 100? This treaty needs to cater far better for what the future might hold.

[Lord Hannan of Kingsclere (Con)]

My Lords, I add my voice to those of the noble and gallant Lords, Lord Craig of Radley and Lord Houghton of Richmond. It seems to me that this is precisely the kind of question that ought to have been looked at in detail. The more we have sat here and gone through clause by clause, the more it seems that these issues were avoided in the negotiations. I wonder whether the Minister has read the report in today’s Times newspaper about where the impetus for this treaty had come from. It quotes a senior figure involved in the administration of the BIOT as saying that it was

“championed by a small number of civil servants”

and that

“in multiple conversations with military and BIOT administration staff it is clear that there is no one who supports this treaty”.

Maybe if we had had those conversations with the people on the ground, military and civil, issues of the kind raised by the noble and gallant Lord, Lord Craig, would have been anticipated, but if they were not, is not the fundamental purpose of this Chamber to address them at this stage? For that reason, should we not be backing the points made by the noble and gallant Lords?