May 2025

Submission to the International Development Committee: Humanitarian Access and Adherence to International Humanitarian Law

Reframing irresponsible arms transfers as a root cause of non-adherence to IHL with knock-on effects on the delivery of aid and humanitarian access

Dr Tomas Hamilton

Barrister, G37 Chambers, London

Adjunct Faculty, University of Amsterdam

The Arms Trade and International Criminal Law (OUP, 2025)

1. This submission draws attention to the irresponsible transfer of conventional arms as a specific root cause of violations of international humanitarian law (IHL). The ready supply of weapons, ammunition, components and dual-use goods into situations where suspected IHL breaches are taking place is increasingly recognised as an enabling factor in those breaches: the topic of better regulation of the arms trade is trending in policy and the study of contemporary armed conflict.
2. In response to an invitation to submit evidence to the Committee, this written evidence addresses these questions:

1. How is the regulation of responsible arms transfers relevant to the UK Government’s role in ensuring the safe delivery of humanitarian assistance?
2. How does UK law currently prohibit arms exports that contribute to IHL breaches?
3. What obligations of due diligence are UK arms companies under to avoid their products being used in IHL breaches?
4. What should the UK Government be doing to encourage arms companies to adhere to export standards and monitor the end use of the items they manufacture?
5. What should government be doing in terms of investigating and holding to account breaches of IHL involving the use of UK manufactured arms and components?

Responsible Arms Transfers and the Safe Delivery of Humanitarian Assistance

What if UK-manufactured arms are being actively used to impede the delivery of UK foreign aid and humanitarian access?

3. The UK faces a broad set of challenges in ensuring its adherence to IHL norms on the international stage. These include regulating its arms export sector to prevent complicity in violating international law.
4. In the Gaza and Yemen conflicts, the responsible regulation of arms transfers – in compliance with IHL standards as required by the Export Control Act – has become intertwined with the safe delivery of humanitarian assistance. The risks of failing to properly regulate the arms trade in compliance with IHL standards tragically ‘came home to roost’ in the Gaza World Central Kitchen (WCK) Attack in April 2024.

Case Study 1: Gaza World Central Kitchen (WCK) Attack (April 2024)

On 1 April 2024, Israeli forces killed seven aid workers—including three British nationals—working for World Central Kitchen in Gaza. The attack was carried out by an Israeli Hermes 450 drone. There is strong suspicion, supported by arms experts and campaigners, that this drone may have been powered by a UK-made engine produced by UAV Engines Limited (UEL), a British subsidiary of Elbit Systems. The UK government has not confirmed or denied whether British-made components were used in this strike, but the possibility remains under scrutiny.

5. It is suspected that UK-manufactured components were used in Israel’s targeted strike that killed aid workers—including British nationals. This raises the scenario where British weapons have not only been used against innocent aid workers and civilians, but are actively impeding the delivery of British aid and overseas development policy.
6. The UK must place at the heart of its arms export policy the avoidance of complicity in international crimes, including attacks against aid workers.

Strengthening the Strategic Export Licensing Criteria in Relation to IHL

7. The Export Control Act 2002 and the Export Control Order 2008 establish strategic controls over military and dual-use goods, prohibiting their export from the UK without a Government-issued licence. The Secretary of State for Business and Trade has overall responsibility for the UK’s export licensing process, including the decision to grant or refuse an export license, and, where necessary, to amend, suspend or revoke extant licences.  Licencing decisions are made on a case-by-case basis against the UK’s Strategic Export Licensing Criteria (SELC), statutory guidance pursuant to section 9(3) of the 2002 Act.[1]
8. The Export Control Act 2002 mandates denial of licenses if there is a “clear risk” that items might be used in IHL violations. The SELC set out that, having assessed the recipient country’s attitude towards relevant principles established by instruments of international humanitarian law, the Government will: “A) Not grant a licence if it determines there is a clear risk that the items might be used to commit or facilitate a serious violation of international humanitarian law. In considering the risk that items might be used to commit or facilitate a serious violation of international humanitarian law, the Government will also take account of the risk that the items might be used to commit or facilitate gender-based violence or serious acts of violence against women or children”. Further, Where Defence provides training or assistance in addition to or alongside the provision of material, there is published guidance on how to ensure this Overseas Security and Justice Assistance (OSJA) work is consistent with human rights obligations and values.[2]
9. There are numerous ways in which Government could strengthen domestic arms export regulation to reduce de facto support for IHL breaches through weapon supplies.

-          There is a mandated role for foreign policy interests in the export process, which could take account of the needs of ensuring adequate delivery of humanitarian aid.  Revisions in 2021 to the Criteria permits an export refusal to be based, exceptionally, on “significant negative impacts on international relations”. The UK’s economic and social interests in delivering foreign aid would appear to fall into the category of ‘significant negative impacts’ through which a licence may be denied.

-          The clearer identification of end users of arms exports. For example, the UK suspended 30 licenses to Israel in 2024 only after prolonged scrutiny of strikes in Gaza, despite earlier evidence of IHL concerns.[3] However, single-issue licences for military goods with an end user in Israel including goods categories covering targeting systems, munitions and military aircraft parts. The UK governemt had previously revoked specific arms cagegories in 2002[4] and 2009[5] but this had not altered broader military support for Israel.

-          Adopt a precautionary principle, halting exports when credible evidence of potential misuse emerges, rather than awaiting definitive proof, akin to interim or injunctive relief that reflects the irremediable and grave nature of the potential harm involved (i.e. the loss of civilian lives). - Freeze licenses immediately upon credible allegations, rather than awaiting ministerial reviews 

-          Publicly disclose the UK governemnt’s risk assessments for all licenses granted to states engaged in active conflicts, as advocated by the Arms Trade Treaty (ATT). Publish risk assessments for all licences, including redacted evidence used to approve exports.

-          Expand suspension criteria to cover all military-linked items, including dual-use technologies, rather than restricting to limited categories

-          Mandate independent audits of arms exports, with findings reported to Parliament

Towards mandatory due diligence for UK arms companies 

10. UK rules demand that where there is a clear risk weapons could be used in unlawful attacks UK authorities must prohibit exports. However, this is not accompanied by a corresponding legal obligation on companies to stop exporting when they are aware of such a clear risk.
11. To the contrary, a 2016 decision of the OECD National Contact Point (NCP) opined that corporations were not under such autonomous due diligence obligations in the UK . The case concerned the supply of munitions by a UK company to Saudi Arabia; Saudi Arabia allegedly used these munitions in an internal security operation which violated human rights. The NCP decided that it is appropriate for the company simply to ‘rely on the UK government export licensing procedure, which includes a human rights risk assessment’.[6] Nonetheless, it bears emphasising that this decision could have been different if the complainants had substantiated their complaint more adequately; after all, the lack of substantiation in relation to the specific incident alleged was the main reason for the NCP’s rejection of the complaint.
12. This approach to corporate due diligence is at odds with European
13. An area of potential UK reform of arms trade law is therefore the enhancement of the independent due diligence requirements of arms companies, even in circumstances where UK regulatory authorities have granted a permissive license to export to an arms manufacturing or arms exporting company.
14. The extent of the due diligence obligations on the UK defence industry in relation to the end use of its products lacks clarity and teeth. In particular, it is unclear whether a positive Government export decision absolves a company of its independent due diligence requirements, or alternatively, merely offers the company a permission to export, leaving the final decision on whether it is safe and responsible to make the export in the hands of the company.
15. While the UK’s ATT Supervisory Risk Assessment framework addresses proliferation financing, it lacks binding requirements for companies to assess IHL compliance.[7] The EU Corporate Sustainability Due Diligence Directive (CSDDD), though currently excluding post-export controls, offers a model for legislating corporate accountability.[8]

-          Enact a Due Diligence Act requiring arms manufacturers to map supply chains, assess end-user risks, and mitigate violations.

-          Carry out necessary reforms to ensure that civil liability for companies that fail to conduct adequate checks, enabling victims to seek redress in UK courts under English tort law if they fail to carry out due diligence responbilty with reference to appropriate standards. Stnadards could be drawan from IHL ,UNGPs, sectoral guidance, the . Liabiliyt would be established by e harm must be reasonably foreseeable as a result of its conduct, the relationship between the victim and the corporation must be ‘sufficiently close’ (‘proximate’), and it must be generally fair, just and reasonable to impose liability.

-          Expand end-use monitoring requirements, obliging companies to report on the deployment of their products in conflict zones.

-          Align export criteria with the Rome Statute’s mens rea standards, requiring firms to demonstrate they did not “know” weapons would facilitate crimes.[9]

-          Real-time monitoring systems to verify weapon deployment, with penalties for diversion or misuse. There is enormous scope for the use of tracing and monitoring technologies to track the actual usage of supplied weapons. Some onus should be on companies to ensure this takes place. This could even be linked to reparations

-          The Strategic Export Licencing Criteria can be revised with language to clarify the nature of the Criteria and the nature of a licence. A license is a permission to export based on the Government’s assessment. A company wanting to export military or dual-use (that could have military or civilian use) goods to other nations must have a licence, but its issuance does not obviate the need for the company to carry out its own due diligence.

-          In addition to clarifying the export framework, the UK Government can look at policy tools to pressure arms companies through financial and legal measures  The government could concider defense contracts and export credit guarantees on adherence to IHL due diligence protocols. Companies with lax compliance records could be barred from public tenders, mirroring the US Leahy Laws’ approach to human rights vetting. Financial institutions, such as pension funds, to divest from firms linked to IHL violations.

Criminal Liability: the Frontier of Complicit Arms Transfers 

16. Under the Rome Statute 1998 individuals who knowingly contribute to international crimes through arms transfers may be prosecuted for complicity.[10] The UK’s International Criminal Court Act 2001 incorporates these provisions but has never pursued such cases.

-          The National Crime Agency should establish a dedicated unit to investigate corporate complicity, collaborating with the ICC’s Office of the Prosecutor to share evidence. Recent precedents, like Dutch prosecutions of executives for supplying chemicals to Saddam Hussein, demonstrate the feasibility of this approach.

-          The scope of accomplice liability under the International Criminal Court Act 2001 could be clarified by explicitly stating that directors may face prosecution for complicity in war crimes, regardless of government licensing.

-          Clarify liability under the International Criminal Court Act 2001, explicitly stating that directors face prosecution for complicity in war crimes, regardless of government licensing.

-          Extend liability to corporate officers who authorize transfers to conflict zones with documented IHL risks.

-          Revise the Bribery Act 2010 to classify IHL violations as “improper conduct,” enabling prosecution of firms bribing officials to secure unlawful exports.

-          Proactive Post-Export Monitoring -  The Arms Trade (Inquiry and Suspension) Bill contains urgent and valuable reforms that would further the UK’s ability to comply with IHL in its arms experts. However, it addresses reform of the licencing process rather than the conduct of companies themselves.

-          The Department for Business and Trade should collaborate with NGOs and UN bodies to investigate alleged misuse of UK arms. The 2024 suspension of licenses to Israel underscores the value of real-time monitoring, but such actions must occur earlier in conflicts.

-          Compel companies to provide targeting data for airstrikes involving UK-made components.

-          Mandate independent audits of arms exports, with findings reported to Parliament

-          Where a recipient is considered particularly high-risk, exports should require parliamentary approval, with a cross-party committee established to review licences flagged by civil society

Conclusion

17. The UK’s adherence to IHL requires systemic reforms to close accountability gaps, enforce corporate due diligence, and prioritize civilian protection over geopolitical interests. By amending flawed legislation, empowering independent investigators, and leveraging legal tools to deter complicit arms transfers, the government can align its practices with its stated commitment to international law. These measures would not only mitigate harm in conflict zones but also reinforce the UK’s leadership in global efforts to uphold humanitarian norms.
18. It is untenable that the UK defence sector should wholly rely on Government to conduct its due diligence and provision should be made for corporations to take responsibility for the end use of their products.

The author is a British barrister and academic in international criminal law, and author of The Arms Trade and International Criminal Law published by Oxford University Press in 2025.