This opinion addresses the legality under international law of the transfer of conventional arms and related equipment to the parties currently engaged in the conflict in Yemen. The opinion does not assess the legality of the export, import or sale of arms to those parties in the light of the domestic law of each supplying State, nor does it consider in detail the obligations of non-state armed groups or of corporate actors in their roles as suppliers and users of arms. The focus here is on the international legal obligations of the parties to the conflict in Yemen and of third States which supply their arms. Set out in the opinion are the main international norms relevant to arms transfer decisions which are necessary for the protection of the civilian population in Yemen and the civilian infrastructure indispensable to its survival.
States that transfer arms to other countries are subject to international legal accountability. They have a duty to withhold such arms transfers when it is reasonably foreseeable the recipients will use the arms for serious violations of international law, or divert them to such end users. This legal opinion explains how those States supplying arms to the parties to the conflict in Yemen bear an enormous responsibility for the large numbers of civilians that have incurred serious injury and loss, including of their homes, resulting in mass internal and external displacement. Civilian infrastructure essential to the survival of the population has been destroyed or seriously damaged in armed attacks, and access to humanitarian aid continues to be impeded by armed forces and militias. According to the United Nations millions are suffering from what it has said is ‘the world’s worst humanitarian crisis’.
The authors have examined the mounting information available relating to the conflicts in Yemen and to international arms transfers made to the parties in those conflicts. They cite credible reports of a systematic pattern of serious and recurring violations of the fundamental rules of international law, violations which continue to be committed by all parties to the conflict in Yemen. Moreover, measures to end impunity and to undertake the necessary institutional reforms that would prevent the repetition of such serious violations have been ineffective. The authors conclude it is reasonable to assume that those States continuing to supply arms, including to the Saudi-UAE coalition forces, have been aware that in the ongoing course of events in Yemen the recipients would almost certainly misuse arms and equipment of the same or similar type and function to commit further serious violations. They are of the view that in the prevailing circumstances such arms transfers are in breach of applicable international law, including Article 6 of the Arms Trade Treaty.