Written questions by Cartlidge.

With reference to page 6 of the Strategic Defence Review: Making Britain Safer: secure at home, strong abroad, published on 2 June 2025, what assessment he has made of the adequacy of submarine docking availability, in the context of his Department’s announcement to produce up to 12 attack submarines.

The Government is committed to ensuring the availability of submarine berths to support all submarine operations. We are focussed on the long-term infrastructure development of His Majesty's Naval Bases Clyde and Devonport to support the United Kingdom's future fleet of submarines.For reasons of operational security, further details on specific berths cannot be disclosed.

Commonwealth and Development Affairs, whether the design of the Chagos Islands flag will change following the ratification of the Chagos treaty.

A British flag will continue to be flown at the UK-US Base on Diego Garcia as it has always done.The British Indian Ocean Territory will cease to exist as a British Overseas Territory upon ratification of the treaty agreed between the UK and Mauritius.No decision has yet been taken on any future use or adaptation of the current BIOT flag.

With reference to page 6 of the Strategic Defence Review: Making Britain Safer: secure at home, strong abroad, published on 2 June 2025, how many years will be covered by the £11bn Invest annual budget.

The Strategic Defence Review (SDR) sets a path for the next decade and beyond to transform Defence.We will develop a new Defence Investment Plan to deliver the SDR’s vision. We will ensure the Plan is deliverable and affordable, considers infrastructure alongside capabilities, enables flexibility to seize new technology opportunities, and maximises the benefits of defence spending to grow the UK economy. This will supersede the old-style Defence Equipment Plan. This will deliver the best kit and technology into the hands of our front-line forces at speed and, importantly, invest in and grow the UK economy. The Defence Investment Plan will be completed later this year. The plan will highlight how the Government's historic investment in defence will deliver warfighting readiness to deter increasing threats and drive defence as an engine for jobs and growth.

With reference to page 6 of the Strategic Defence Review: Making Britain Safer: secure at home, strong abroad, published on 2 June 2025, whether the £15bn investment in the sovereign warhead programme will solely cover the cost of developing the sovereign warhead.

The £15 billion investment in the sovereign warhead programme this Parliament includes sustaining our existing stockpile, developing Astraea; our sovereign replacement warhead programme, and modernising our infrastructure. We will uphold our commitments as a responsible nuclear weapons state.

Whether he plans to hold discussions with local authorities that have voted to divest pension funds from UK defence companies.

The Government is committed to increasing private sector investment in the UK defence sector, recognising its vital role in driving innovation, creating jobs, and enhancing national security. The Strategic Defence Review (SDR) recommended the Ministry of Defence develop a dedicated financial services strategy by March 2026. We will consult a wide range of stakeholders during the production of this strategy.

What steps he is taking to encourage local authorities to invest pension funds in UK defence companies.

The Government is committed to increasing private sector investment in the UK defence sector, recognising its vital role in driving innovation, creating jobs, and enhancing national security. This commitment was underscored by the Defence Secretary’s speech at the London Stock Exchange on 13 May 2025, the roundtable he chaired with private investors on 2 April, and the establishment of the UK Defence Economic and Growth Taskforce, chaired by the Defence Secretary and the Chancellor.The Strategic Defence Review recommended the Ministry of Defence develop a dedicated financial services strategy by March 2026. We will consult a wide range of stakeholders during the production of this strategy.

Pursuant to the Answer of 6 June 2025 to Question 56289 on Ministry of Defence: Documents, what time on 18 July 2023 the Shadow Secretary of State for Defence (a) was sent and (b) received from his Department’s messenger service and (c) was permitted access to an embargoed copy of his Department’s policy paper entitled Defence command paper 2023: defence’s response to a more contested and volatile world, published on 18 July 2023.

Officials have been unable to locate information which goes beyond that provided in my answer to the hon. Member's Question (56289).

Whether UK defence companies received briefings on the contents of the Strategic Defence Review prior to 2 June 2025.

For the launch of the Strategic Defence Review, the Government offered embargoed briefings to our people and senior defence leaders, plus certain Parliamentarians, trade unions, businesses, allies and media. This was broadly consistent with the approach for previous defence reviews.

When he authorised his Department to issue unredacted hard copies of the Strategic Defence Review for viewing by journalists at 10.30am in Horse Guards on 2 June 2025.

For the launch of the Strategic Defence Review, the Government offered embargoed briefings to our people and senior defence leaders, plus certain Parliamentarians, trade unions, businesses, allies and media. This was broadly consistent with the approach for previous defence reviews.

What estimate he has made of the potential impact of the UK/Mauritius: Agreement concerning the Chagos Archipelago including Diego Garcia, published on 22 May 2025, on the level of contributions from the United States for the costs of running the military base on Diego Garcia.

The US continues to pay for the operating and maintenance costs of the Naval Support Facility on Diego Garcia. Our initial assessment is that the UK/Mauritius Agreement is unlikely to have any significant impact, in the short-term, on the operating and maintenance costs of the Naval Support Facility on Diego Garcia.

How much the United States contributed to the running cost of the Diego Garcia military base in the most recent financial year for which information is available.

As agreed in the US-UK Exchange of Notes which governs the US use of Diego Garcia, there is no direct payment between the US and the UK for use of the base. The US pays for the operating and maintenance costs of the Naval Support Facility on Diego Garcia.

Whether he has authorised any changes to the proposed timetable for the delivery of the multi-role strike ship since 5 July 2024.

The Multi Role Strike Ship (MRSS) programme is in the Concept Phase. It is funded from the Defence budget to enable the Royal Navy and Defence Equipment and Support (DE&S) to conduct detailed preparatory work with intent to deliver first of class in 2033. The Programme will submit an Outline Business Case in late 2025 and is working closely with the UK shipbuilding industry and the National Shipbuilding Office to deliver best value for money for the Navy and the Nation.

With reference to recommendation 5 of the Strategic Defence Review: Making Britain Safer: secure at home, strong abroad, published on 2 June 2025, when he plans to launch a tender to deliver the Digital Targeting Web.

The Digital Targeting Web is not a single piece of equipment or software with a single supplier, but an ecosystem that will bring together the current disparate multitude of targeting systems and software into a secure and efficiently connected, cross-classification, capability that will enable warfighting at pace and scale across all 5 operational domains on the Digital Backbone. It will easily enable the introduction of emerging and novel technology, improve data-standardisation to enable better data and information sharing so that Defence has a much-improved ability to understand and shape the battlespace. Through the automation of processes, and the more timely provision of targeting data to weapon systems, the DTW will ensure the end-to-end targeting cycle is accelerated to better support commanders and provide UK Defence with a warfighting advantage over our adversaries. There will be no ‘single supplier’ nor tender to deliver the Digital Targeting Web, but a series of accelerators will be spun up to achieve the DTW. The first industry day has been set up for 18 July 2025 where industry can find out more about the approach and potential opportunities.

With reference to Article 10, Clause 1 of the document entitled UK/Mauritius: Agreement concerning the Chagos Archipelago including Diego Garcia (CS Mauritius No.1/2025), published on 22 May 2025, whether the annual sum referred to will come solely from his Department's budget.

The funding arrangements for the treaty are subject to the Spending Review, which will be completed on 11 June.

With reference to Article 11, Clause 1 of the UK/Mauritius: Agreement concerning the Chagos Archipelago including Diego Garcia [CS Mauritius No.1/2025], what the annual sum paid to Mauritius is in cash terms.

The schedule of payments is set out in the finance exchange of letters that was published alongside the treaty. The estimated average annual payment value is £101 million over the initial 99-year period of the treaty. This has been calculated using the standard formula set out in the Green Book that the government uses for all long-term projects. These calculations have been agreed by the Government Actuary’s Department. The full details are in the Explanatory Memorandum laid alongside the Treaty.

With reference to Article 14, Clause 3 of the UK/Mauritius: Agreement concerning the Chagos Archipelago including Diego Garcia [CS Mauritius No.1/2025], under what circumstances a concern relating to the essential security interests of the implementation of the Agreement would be made.

Article 14 of the Treaty sets out the role of the Joint Commission in resolving disputes. It is expected that the majority of security concerns that arise once the Agreement is in force will be resolved via the Joint Commission. As stated in Annex 1, paragraph 10, in the event that the UK has serious concerns that a proposed activity by Mauritius risked conflicting with the obligations in Article 3(2)(b), the UK may raise that concern at the political level for urgent consultations.

With reference to Annex 1, Clause 2, of the document entitled UK/Mauritius: Agreement concerning the Chagos Archipelago including Diego Garcia (CS Mauritius No.1/2025), published on 22 May 2025, whether Mauritius will be required to confirm receipt of advanced notice of any armed attack on a third state emanating from the Base.

As the hon. Gentleman will recall from his time as a Defence Minister, it is standard practice for basing arrangements to include an agreement to inform a host nation about military action from their territory. As any notification of an armed attack from the base will take place after the event, a confirmation of receipt is not required.

With reference to Annex 1, Clause 2, of the document entitled UK/Mauritius: Agreement concerning the Chagos Archipelago including Diego Garcia (CS Mauritius No.1/2025), published on 22 May 2025, what the agreed advanced timing is to inform Mauritius of any armed attack on a third state emanating from the Base.

As the hon. Gentleman will recall from his time as a Defence Minister, it is standard practice for basing arrangements to include an agreement to inform a host nation about military action from their territory. Additionally, the UN Charter has a requirement to notify the UN of military action taken in self-defence. Any notification to Mauritius will take place after the event and will not require the UK to divulge sensitive information. The United Kingdom will inform Mauritius through normal diplomatic channels.

With reference to Annex 1, Clause 3, of the UK/Mauritius: Agreement concerning the Chagos Archipelago including Diego Garcia [CS Mauritius No.1/2025], whether permission will be required from Mauritius to (a) upgrade and (b) maintain equipment on the base.

As stated in Annex 1, paragraph 1 of the Treaty, the United Kingdom will have unrestricted ability to authorise the installation, operation, and repair of new and existing systems on Diego Garcia, without the need to give notification. In respect of the Chagos Archipelago beyond Diego Garcia, Annex 1, paragraph 3 states that the UK shall have rights of access to maintain and upgrade equipment after notification to Mauritius. There is no requirement to seek permission in either scenario. With the robust security provisions negotiated under this agreement, the UK maintains full operational control of the military base on Diego Garcia.

With reference to Annex 1, Clause 3, of the UK/Mauritius: Agreement concerning the Chagos Archipelago including Diego Garcia [CS Mauritius No.1/2025], whether any States, excluding the United States of America, will operate alongside the UK on the Diego Garcia military base.

Annex 1, paragraph 1 of the Treaty confirms that the United Kingdom will have unrestricted ability to control the deployment of any military, civilian and contract personnel to Diego Garcia. Annex 1, paragraph 3 of the Treaty states that for the Chagos Archipelago beyond Diego Garcia, states operating with the UK and US will also have unrestricted rights, save for overflight or undersea access which require prior notification to Mauritius. We will overall retain the ability to collaborate with our allies through the base on Diego Garcia.