In his illuminating long read (‘They couldn’t do it without us’: the UK’s role in Yemen’s deadly war, 18 June), Arron Merat describes the increasingly shaky claims made by ministers that the UK is not a party to the Yemen conflict (despite the UK posting personnel to prepare and maintain Saudi Arabian fighter jets, and sending UK special forces to fight on the side of the Saudi-led coalition). Such claims are clearly designed to avoid responsibility under rules of the Geneva conventions and other international humanitarian law that bind parties to conflict.
Under the international law of state responsibility, however, the UK could still be liable for “aiding and assisting” another state that committed an internationally wrongful act or maintained a serious breach of a peremptory norm of international law. The overwhelming evidence collected on the ground by Mwatana, Ceasefire’s partner organisation cited by Arron Merat, testifies to gross and systematic violations including repeated airstrikes against schools, hospitals, markets, farms and food storage sites, far from any military objective.
In Iraq and Syria, as well as Yemen, the UK government has adopted a strategy of pursuing military objectives “by, with or through” partner forces. While such a strategy may limit the military exposure of UK forces, it should not limit the UK’s liability for aiding devastating violations against civilians.