On 1 March 2026, the leaders of the United Kingdom, France and Germany condemned recent Iranian missile and drone attacks across the region, describing them as indiscriminate and disproportionate and warning that allied civilians and service personnel had been put at risk, including in states not involved in initial US and Israeli operations. (gov.uk)
The leaders called for an immediate halt to Iranian attacks and signalled they would defend their interests and those of regional allies. The statement said this could include enabling necessary and proportionate defensive measures to disable Iranian missile and drone capability at source, and confirmed coordination with the United States and regional partners. (gov.uk)
The formulation represents a sharper posture than the E3 note published on 28 February 2026, which condemned Iranian strikes and emphasised that the three countries did not participate in the US‑Israeli action but did not reference disabling capabilities at source. The 1 March text adds potential enabling of defensive action, while reaffirming cooperation with partners. (gov.uk)
The E3 is the established UK‑France‑Germany coordination format on Iran policy. In 2025 the three governments jointly triggered the “snapback” mechanism under UN Security Council Resolution 2231 in response to Iranian non‑compliance, leading to the re‑instatement of earlier UN measures from 27 September 2025-context that underlines sustained E3 alignment on Iran. (iranintl.com)
Any move to enable action “at source” sits within the international law framework on self‑defence. Article 51 of the UN Charter recognises the inherent right of individual or collective self‑defence in the event of an armed attack, requires that measures be reported to the UN Security Council without delay, and that they cease once the Council has taken necessary steps. (un.org)
UK government statements on the use of force in self‑defence emphasise necessity and proportionality as controlling tests, including in collective self‑defence, and characterise force as a last resort against a direct and imminent threat. Those positions, articulated by the Attorney General in public speeches, provide the reference points for any UK contribution to defensive measures. (gov.uk)
Operationally, enabling defensive action can span intelligence cooperation, air and missile defence support, basing and overflight permissions, and-where legal thresholds are met-limited action to disable launch systems or associated infrastructure. Any destructive action would be constrained by the law of armed conflict, including the rules on distinction and proportionality and the obligation to minimise incidental harm. (gov.uk)
The E3’s commitment to work with the United States and regional allies indicates a coordinated approach to threat assessment, force protection and, if required, collective self‑defence measures. Should any state act under Article 51, formal notification to the Security Council would clarify scope and justification; practitioners should watch for such filings alongside practical steps to protect nationals and stabilise the theatre. (gov.uk)