Diego Garcia Military Base and British Indian Ocean Territory Bill

Baroness Goldie Excerpts

Tuesday 25th November 2025 Lords Chamber

[Lord Callanan (Con)]

My Lords, the amendments in this group speak to perhaps one of the most concerning parts of the treaty—although the previous bit was also concerning: namely, the risk that this agreement will undermine our security. Given the large number of amendments in this group, I will speak only to those in my name. I know that my noble friend Lady Goldie will speak to her amendments as well, and I will certainly not seek to pre-empt her arguments in my remarks, as my noble friend is much more of an expert on defence matters than I will ever be.

My Amendment 18 is a commencement block that would prevent the main clauses of the Bill coming into effect until the Government have laid a report on securing a guarantee that all non-UK and non-US civilian personnel stationed on the archipelago will benefit from the provisions of Annex 1. Annex 1 protects the UK’s unrestricted access to Diego Garcia’s sea and airspace. The treaty makes reference to some civilian activity, but we are seeking an assurance from the Government that that part of the treaty in its entirety applies to civilians stationed on Diego Garcia. I hope the Minister will be able to give us that assurance.

Amendment 67 speaks to one of the most fundamental questions, which has already been the subject of much debate. The treaty is clear that the UK must inform Mauritius of any armed attack on a third state directly emanating from the base on Diego Garcia, using the magnificent word, “expeditiously”. The dictionary definition of expeditiously is “quickly and efficiently” and “with speed”. Many have rightly asked what expeditiously means in practice. My Amendment 67 clarifies that the UK Government must not inform Mauritius of any relevant armed attacks until the attack has ended. Providing prior notification to Mauritius, or indeed any third state not directly involved in the attack, could risk the safety of British and American servicemen who are engaged in the relevant operation. Could the Minister confirm that nothing in the treaty requires the UK Government to give forewarning of any attack emanating from the military base? If that is the case then I am sure they can accept the amendment.

Additionally, my amendment seeks a requirement not to notify Mauritius if notification would endanger the security of the base. Can the Minister confirm that nothing in the treaty would prevent the Government withholding notification if notifying Mauritius would endanger the base? My noble friend Lady Goldie will be going into additional details on these important issues.

Amendment 69 in my name seeks to make a point about the location of specific equipment and installations on the base. It is essential that the security of the base is maintained. It would not be acceptable if the UK Government were to endanger the security of equipment at the military base by notifying Mauritius. In replying to the debate, can the Minister please address those concerns? It is essential that the UK Government have the right to refuse notification when doing so would endanger the base itself or our personnel.

[Baroness Goldie (Con)]

My Lords, I associate myself with the remarks of my noble friend Lord Callanan on the amendments to which he spoke. I shall be dealing with the word “expeditiously” and I will try to ensure that that characterises my contribution, and perhaps influences this debate.

I wish to speak to my Amendments 83, 85, 86 and 87. At Second Reading, I raised the issue of the mismatch between the Bill and the treaty that it implements. My main concern in this whole affair is our defence and security and the implications of this Bill on that. I identified a range of areas where greater clarity is required. Before I continue, I should say that I have received a letter from the Ministers, for which I thank them. That sought to clarify some of the questions that I asked at Second Reading. The letter brings a degree of clarification, but in other respects it leaves me with questions. I shall address these as I explain my amendments.

Amendment 83 is simply a technical drafting amendment to accommodate my remaining amendments in this group. It specifies that the commencement of the treaty cannot occur until the conditions outlined in my amendments have been satisfied.

Amendment 85 relates to the specific notification requirements under Annex 1 1(b)(viii) of the treaty. My amendment would require that Clauses 2 to 4 do not come into force until the Secretary of State has published a statement establishing that the notification in Annex 1 1(b)(viii) of the treaty does not require the consent of Mauritius in response. The provision in Annex 1 to which this refers says that:

“In accordance with this Agreement and with reference to Article 2(5) and Annex 2, in respect of Diego Garcia, Mauritius agrees the United Kingdom shall have … unrestricted access, basing and overflight … for non-United Kingdom and non-United States of America aircraft and vessels, upon notification to Mauritius”.


The amendment seeks to enable the Secretary of State to make explicit, before Clauses 2 to 4 of the Bill can come into force, that the consent of Mauritius is not required for us to host third-party forces on Diego Garcia.

As I mentioned, I have the letter from the Ministers in which they helpfully clarify that permission from Mauritius is not required. However, I require the Minister to confirm that such notification is after the event. If notification is required before the event, that implies consent is required, or that the intimation of an objection by Mauritius is possible. That is why I seek the clarification.

We cannot have a situation where Mauritius can in any way object to which forces are present at the base. The operation of the base, including the matter of the basing of our allies, must be solely at the discretion of the United Kingdom. I would appreciate the Minister giving a guarantee that Mauritius will have no control whatever over the basing and overflight of other countries’ forces. Unusually, the Minister and I are perhaps nearly at consensus in idem here. If that is the case, why would the Secretary of State be reluctant to publish a statement?

Amendment 86 is another defence and security amendment. It seeks that Clauses 2 to 4 would not come into force until the Secretary of State has published a statement establishing that the obligation under Annex 1(2) of the treaty

“does not extend to aircraft and vessels which have landed or docked at the Base for the purposes of maintenance or refuelling prior to the armed attack on a third state”.

Annex 1(2) of the treaty is the provision that requires the United Kingdom

“to expeditiously inform Mauritius of any armed attack on a third State”.

As we have discussed, much has been made of what is meant by “expeditiously”. The Ministers’ letter to me stated that they are satisfied that this does not require the UK to seek the permission of Mauritius, nor for notification to be given prior to the event. That is helpful. The International Agreements Committee of this House has also concluded that it interprets “expeditiously” to mean

“as soon as reasonably practicable in the circumstances”.

I believe that the Minister gives her interpretation in good faith, but what of Mauritius’s interpretation? Does the Minister know whether the Mauritian Government share this view? If she does not currently know, and I quite accept that she may not, I would be happy for her to write to me to confirm the point.

--- Later in debate ---

I say to the noble Lord, Lord Weir, that these provisions have been discussed and approved at the highest levels of the US security apparatus. Both the IAC and the IRDC have scrutinised them. This treaty specifically confers—

[Baroness Goldie (Con)]

Forgive me for being slightly behind the curve; I was trying to follow the sections in the annex. The Minister referred to Annex 1(11), in particular the definition of “unrestricted”. That paragraph states that

“‘unrestricted’ means not requiring permission or notification, subject to the standing authorisations and notifications separately agreed between the Parties to meet the requirements of international or domestic Mauritian law or current practice”.

For the sake of clarification, what are these “standing authorisations and notifications”?

[Lord Coaker (Lab)]

If I am wrong on this, I will write to the noble Baroness and put a copy in the Library so that all Members can access it. My understanding is that the crucial bit of Annex 1(11)(c) is

“‘unrestricted’ means not requiring permission or notification”.

The phrase,

“the standing authorisations and notifications separately agreed between the Parties”,

refers to things contained within the treaty. I will write to the noble Baroness to clarify that. I am grateful to her for pointing it out.

The fundamental point I am trying to make—which I think the noble Baroness and the noble Lord, Lord Ahmad, made—is that we have an obligation under the treaty to notify Mauritius of activities emanating from the base but we do not have to seek its permission. “Expeditiously” notifying does not mean notifying before we take any agreed action. Those were the points that I thought the noble Baroness was making, but I will certainly seek to clarify exactly where that takes us with Annex 1(11)(c). I will write to the noble Baroness and provide a copy to others. I thank her for raising that.

The treaty specifically confers on the UK the unrestricted ability to

“control the conduct and deployment of armed operations and lethal capabilities”

in respect of Diego Garcia. Given that there is no question over operational freedom on Diego Garcia, it is unclear what necessary derogations the noble Lord, Lord Kempsell, is seeking. The annex gives the UK the extensive rights that we would need in such a situation.

The noble Lord, Lord Kempsell, raised reporting restrictions. His Majesty’s Armed Forces and the intelligence services routinely produce reports for the Prime Minister on all types of security matters. I reassure the noble Lord, and other noble Lords, that this will include operational issues arising on the Diego Garcia base. There is no requirement for this to be made a statutory obligation, as Amendment 81E seeks to do. Additionally, Amendment 81F would represent an unusual interference with the prerogative to conduct international affairs and to make or unmake treaties. Noble Lords will understand that there is often a need for confidentiality in international discussions.

The clock is flashing away and the Whip is getting jumpy next to me. I shall have a look at Hansard and I shall write to noble Lords in the debate with anything that I have not covered and any questions that have not been answered and make sure that the amendments that I have not responded to are responded to. I shall send the letter to noble Lords in the debate. Let me be clear: I shall write to noble Lords about two or three of the amendments that I have not covered, copy the letter to noble Lords and put a copy in the Library. I hope that that is acceptable to everyone.

I thank noble Lords for a really interesting and important debate on the security provisions of the treaty and ask the noble Lord to withdraw his amendment.