Approximate read time: 11 minutes

On 23 October 2024, the House of Lords is scheduled to debate the following reports from the House of Lords International Agreements Committee:

Lord Goldsmith (Labour), the committee’s current chair, will sponsor motions that will allow the House to ‘take note’ of these reports which will be debated together.

1. What is the role of the House of Lords International Agreements Committee?

The House of Lords International Agreements Committee scrutinises all treaties that are laid before Parliament under the terms of the Constitutional Reform and Governance Act 2010 (CRAG Act 2010). It also considers the government’s conduct of negotiations with states and other international partners.

There is no systematic scrutiny function for the UK Parliament during the negotiation and agreement of a treaty. However, Parliament does have a role in the process of ratification. Although no debate or vote in either House of Parliament is required prior to a treaty being ratified, under the CRAG Act 2010 treaties are laid before Parliament for 21 days before they can be ratified.[1] The House of Lords can vote against ratification, but the government can still proceed by making a statement setting out why it believes the treaty should be ratified. The House of Commons has additional powers to delay ratification. Further information on the scrutiny of international treaties by the House of Lords is provided in the House of Lords Library briefing ‘Parliamentary scrutiny of treaties’, 16 May 2023.

2. What is the UK-US Mutual Defence Agreement?

The UK-US cooperation agreement on the uses of atomic energy for mutual defence purposes, also known as the UK-US mutual defence agreement (MDA), allows for the transfer of nuclear materials, technology and information between the UK and the US.[2] The agreement also allows for the sale by the US to the UK of submarine nuclear propulsion plant and materials.[3] However, it does not allow for the transfer of nuclear weapons.[4] The agreement effectively underpins the defence nuclear relationship between the UK and US.[5]

The UK-US MDA was signed in 1958 and came into force in the same year. Since that time the UK has relied on US technological support and expertise in order to support its nuclear deterrence capabilities.[6] The UK-US MDA has been amended several times since it was agreed. One of the most significant amendments was the addition of article III bis, introduced in 1959.[7] Article III bis allowed for the transfer of special nuclear materials and non-nuclear components between the US and the UK.[8] Unlike the rest of the UK-US MDA, article III bis is time-limited and must be extended in order to remain in force. Since 1980, the requirement has been for article III bis to be extended every ten years. Article III bis was last amended in 2014 and will expire on 31 December 2024 if it is not extended.[9]

Further information on the UK-US MDA is provided in the House of Commons Library briefing ‘Amendments to the UK-US Mutual Defence Agreement’, 6 September 2024. An annotated version of the bill detailing these amendments since 1958 is provided in the Nuclear Information Service briefing, ‘US-UK Mutual Defence Agreement’, July 2024. As noted by the House of Commons Library, articles IX and X of the UK-US MDA are excluded from this briefing but they have remained largely unchanged since the original treaty was signed in 1958.[10]

3. How are the UK and the US proposing to amend the UK-US Mutual Defence Agreement?

In July 2024, the UK Labour government published the text of a proposed agreement with the US to amend the UK-US MDA.[11] The suggested agreement proposed several minor and technical amendments to the existing text. However, at the same time, articles 4 and 5 of the agreement would make the following substantive changes to article III and article III bis of the UK-US MDA:

  • Articles 4 of the amendment agreement would amend article III of the UK-US MDA to allow for reciprocal cooperation between the UK and the US in relation to naval nuclear propulsion. This would allow for the transfer of nuclear propulsion plants and/or parts between the UK and the US. It would also extend the provisions in article III to apply to naval vessels more broadly beyond submarines.
  • Article 5 would remove the provisions requiring article III bis of the UK-US MDA to be extended, ending the requirement for this article to be renewed every 10 years.

The government has said article 4 of the amendment agreement would enable the UK and the US to provide equipment on a reciprocal basis if the two countries wished to do so in future.[12] However, in his evidence to the House of Lords International Agreements Committee in October 2024, Director of Strategy and Policy for the Defence Nuclear Organisation at the Ministry of Defence Joe Pitt‑Rashid said the UK and the US did not currently have a “programmatic intent” to make use of this provision.[13] The government has said article 5 of the amendment agreement would secure continued cooperation with the US in the field of defence technology.[14] Mr Pitt‑Rashid told the committee that the removal of the time limit would bring article III bis in line with the rest of the UK-US MDA.[15] Responding to concerns from the committee regarding how this might affect parliamentary oversight of the UK-US MDA, he said that the government had a “firm commitment” to ensure “transparency and accountability to parliament within the limits of national security”.[16]

The proposed amendment agreement was laid before Parliament on 26 July 2024. The scrutiny period under the CRAG Act 2010 for the agreement ends on 23 October 2024.[17] This agreement is also currently undergoing a ratification process in the US Congress.[18]

4. What is the treaty on AUKUS naval nuclear propulsion?

The AUKUS agreement is a trilateral security partnership between the UK, the US and Australia agreed in 2021.[19] The agreement was designed to allow these three countries to cooperate closely on key defence capabilities, including submarine technology. The agreement consists of two pillars:

  • Pillar 1 focuses on supporting Australia to acquire its first conventionally armed, nuclear-powered submarine fleet. It does not involve the transfer of nuclear weapons to Australia.
  • Pillar 2 focuses on cooperation in eight advanced military capability areas: artificial intelligence, quantum technologies, innovation, information sharing, and cyber, undersea, hypersonic and counter-hypersonic and electronic warfare domains.

The AUKUS Naval Nuclear Propulsion Cooperation Agreement (NNPCA) forms part of pillar one of the AUKUS agreement. It would allow for the sharing of naval nuclear propulsion information as well as allowing the transfer of related material and equipment. When it comes into force it will supersede the existing agreement—the Exchange of Naval Nuclear Propulsion Information Agreement (ENNPIA).[20] The ENNPIA was concluded in November 2021 and entered into force in January 2022. It provided for the exchange of information on naval nuclear propulsion during the initial 18-month scoping phase of the AUKUS submarine programme. Further information on the ENNPIA is provided in the House of Lords Library briefing ‘AUKUS agreement to exchange naval nuclear propulsion information’, 14 January 2022. The government has said the new agreement is necessary in order to enable the UK to continue to support Australia in building a nuclear-powered submarine fleet using technology from the UK and the US.[21]

The AUKUS NNPCA was published and laid before Parliament on 2 September 2024.[22] The scrutiny period is scheduled to end on 29 October 2024.[23]

5. What did the international agreements committee conclude?

The House of Lords International Agreements Committee reported the amendments to the UK-US MDA to the House of Lords for “special attention” on the grounds that they were politically significant and gave rise to questions of public policy the House might wish to debate.[24] The committee said the proposed amendments would mean the UK-US MDA would no longer be subject to “routine parliamentary scrutiny”.[25] The committee described the loss of regular parliamentary oversight as “regrettable” and called on the government “to commit to providing a report to Parliament on the progress and operation of the MDA every ten years”.[26] The committee also noted the amendment agreement would receive greater scrutiny in the US Congress than was possible in Parliament under the CRAG Act 2010.[27] It criticised the process for scrutiny under the CRAG Act, arguing:

In light of the MDA’s role in forming the cornerstone of the UK-US defence and security relationship, we regret the lack of sufficient time to take evidence on this important agreement.[28]

The committee also reported the AUKUS NNPCA for the special attention of the House.[29] The committee’s report did not include any further conclusions or recommendations, although the committee did note the “significant progress” that had been made in the delivery of pillar one of the AUKUS partnership since 2021.[30]

6. Read more


Cover image UK MOD © Crown copyright 2024.

References

  1. Constitutional Reform and Governance Act 2010, part 2. Return to text
  2. HM Government, Agreement between the Government of the United Kingdom of Great Britain and Northern Ireland and the Government of the United States of America for Co-operation on the Uses of Atomic Energy for Mutual Defence Purposes, 3 July 1958, Cmnd 537. Return to text
  3. As above, article III, as amended. Return to text
  4. As above, article V. Return to text
  5. Foreign, Commonwealth and Development Office, ‘Explanatory memorandum on the amendment to the Agreement between the Government of the United Kingdom of Great Britain and Northern Ireland and the Government of the United States of America for Cooperation on the Uses of Atomic Energy for Mutual Defence Purposes’, 26 July 2024, p 1. Return to text
  6. House of Lords International Agreements Committee, ‘Scrutiny of International Agreements: Amendment to the UK-US Agreement for Cooperation on the Uses of Atomic Energy for Mutual Defence’, 17 October 2024, HL Paper 20 of session 2024–25, p 4. Return to text
  7. ‘Bis’ is used to indicate this is the second article with the same number in an existing treaty.((Oxford Reference, ‘Bis’, accessed 16 October 2024. Return to text
  8. The text of article III bis is reproduced in the House of Commons Library briefing ‘Amendments to the UK-US Mutual Defence Agreement’, 6 September 2024, pp 8–9. Return to text
  9. Foreign, Commonwealth and Development Office, ‘Explanatory memorandum on the amendment to the Agreement between the Government of the United Kingdom of Great Britain and Northern Ireland and the Government of the United States of America for Cooperation on the Uses of Atomic Energy for Mutual Defence Purposes’, 26 July 2024, p 1. Return to text
  10. House of Commons Library, ‘Amendments to the UK-US Mutual Defence Agreement’, 6 September 2024, p 10. Return to text
  11. Foreign, Commonwealth and Development Office, ‘UK/USA: Amendment to the Agreement for Cooperation on the Uses of Atomic Energy for Mutual Defence Purposes [CS USA No.1/2024]’, 26 July 2024. Return to text
  12. House of Lords International Agreements Committee, ‘Scrutiny of International Agreements: Amendment to the UK-US Agreement for Cooperation on the Uses of Atomic Energy for Mutual Defence’, 17 October 2024, HL Paper 20 of session 2024–25, p 46. Return to text
  13. House of Lords International Agreements Committee, ‘Corrected oral evidence: Amendments to the UK-US mutual defence agreement’, 8 October 2024, Q3. Return to text
  14. House of Lords International Agreements Committee, ‘Scrutiny of International Agreements: Amendment to the UK-US Agreement for Cooperation on the Uses of Atomic Energy for Mutual Defence’, 17 October 2024, HL Paper 20 of session 2024–25, p 46. Return to text
  15. House of Lords International Agreements Committee, ‘Corrected oral evidence: Amendments to the UK-US mutual defence agreement’, 8 October 2024, Q8. Return to text
  16. As above. Return to text
  17. House of Lords International Agreements Committee, ‘Scrutiny of International Agreements: Amendment to the UK-US Agreement for Cooperation on the Uses of Atomic Energy for Mutual Defence’, 17 October 2024, HL Paper 20 of session 2024–25, p 3. Return to text
  18. As above, p 8. Return to text
  19. Prime Minister’s Office, ‘UK, US AND Australia launch new security partnership’, 15 September 2021. Return to text
  20. Foreign, Commonwealth and Development Office, ‘UK/Australia/USA: Agreement for the Exchange of Naval Nuclear Propulsion Information [MS No.8/2021]’, 29 November 2021. Return to text
  21. Ministry of Defence, ‘AUKUS trilateral statement: 8 August 2024’, 8 August 2024. Return to text
  22. Foreign, Commonwealth and Development Office, ‘Agreement among the Government of the United Kingdom of Great Britain and Northern Ireland, the Government of Australia, and the Government of the United States of America for Cooperation related to Naval Nuclear Propulsion’, 2 September 2024, CP 1148. Return to text
  23. House of Lords International Agreements Committee, ‘Scrutiny of International Agreements: The AUKUS Naval Nuclear Propulsion Cooperation Agreement’, 17 October 2024, HL Paper 21 of session 2024–25, p 3. Return to text
  24. House of Lords International Agreements Committee, ‘Scrutiny of International Agreements: Amendment to the UK-US Agreement for Cooperation on the Uses of Atomic Energy for Mutual Defence’, 17 October 2024, HL Paper 20 of session 2024–25, p 13. Return to text
  25. As above, p 2. Return to text
  26. As above, p 12. Return to text
  27. As above, p 9. Return to text
  28. As above. Return to text
  29. House of Lords International Agreements Committee, ‘Scrutiny of International Agreements: The AUKUS Naval Nuclear Propulsion Cooperation Agreement’, 17 October 2024, HL Paper 21 of session 2024–25, p 2. Return to text
  30. As above, p 8. Return to text