The UK Ministry of Defence confirmed on 13 March 2026 that Defence Secretary John Healey and Ireland’s Minister for Defence Helen McEntee have signed an updated Memorandum of Understanding on bilateral defence cooperation. The announcement coincided with the UK–Ireland Leaders’ Summit in Cork between the Prime Minister and Taoiseach Micheál Martin, underscoring top‑level backing for closer day‑to‑day collaboration (UK Ministry of Defence press release, 13 March 2026).
According to the UK Government communication, the refreshed MoU concentrates on four practical areas: enhanced maritime cooperation to protect critical undersea infrastructure and improve incident response; strengthened cyber defence cooperation; information sharing in the air domain to improve joint situational awareness; and exploring options for joint procurement, including Government‑to‑Government sales.
Maritime cooperation is the most detailed strand. The MoU indicates that the UK Armed Forces and the Irish Defence Forces will increase coordination on maritime security to protect critical subsea assets and agree improved mechanisms for responding to maritime security incidents. This places explicit emphasis on resilience planning for infrastructure that supports energy and data flows between the islands.
In the cyber and air domains, the document commits both governments to deepen information exchange, enhance shared threat pictures and raise operational resilience. The stated purpose is to improve joint situational awareness so that authorities can detect, assess and respond to threats more quickly while maintaining national control of decision‑making.
On procurement, the MoU mandates officials to examine potential areas of joint demand and to consider whether Government‑to‑Government sales routes could be appropriate for specific capability needs. This is framed as exploratory work rather than a pre‑determined programme, giving procurement teams scope to test feasibility within existing budget and approvals processes.
The agreement also reiterates existing areas of cooperation: UN peacekeeping, crisis management and humanitarian operations, along with training, military education and staff exchanges. It references continued support for Ukraine through the Coalition of the Willing, reflecting ongoing alignment on European security priorities as stated by both governments.
The 2026 text replaces the 2015 MoU signed by then Defence Secretary Michael Fallon and Minister Simon Coveney. The Ministry of Defence notes that the update fulfils a commitment made at the 2025 UK–Ireland Leaders’ Summit to modernise the framework in line with an evolving bilateral partnership and a changing threat environment (UK Ministry of Defence press release, 13 March 2026).
Government messaging makes clear that the cooperation framework operates with full respect for each country’s defence and security policies. Irish ministers have repeatedly underlined that Ireland will strengthen security while maintaining its policy of neutrality; the MoU expressly states that cooperation proceeds in a way that respects these distinct policies.
No new legal obligations are created by the announcement itself; rather, it sets direction for departments and armed forces to progress workstreams through existing bilateral channels. Specific technical arrangements are not detailed in the press release, indicating that further administrative instruments and guidance will follow as officials translate the framework into operational practice.
For policy and industry readers, the immediate takeaways are pragmatic. Expect closer routine coordination at sea around infrastructure protection and incident response, more structured cyber and air data‑sharing to support a common operating picture, and an official channel to test joint procurement where it can demonstrably add value. All of this sits within clearly stated national sovereignty and policy boundaries.