Résumé : The report will demonstrate that under existing international law the EU and its member states have the obligation to refrain from any form of trade or economic relations with Israeli companies established or conducting activities in Palestinian territories. This obligation arises from customary principles that govern States’ international responsibilities and set out the consequences, for third States, of serious breaches of peremptory norms of international law. We will first describe how the Israeli government’s settlement policy in the occupied Palestinian territory implies serious and systematic breaches of obligations that stem from fundamental norms of international law (I).Breaches of international law by Israel imply legal consequences for third States, namely the obligations to “ensure respect” for international law, “to not recognise” an illegal situation arising from such breaches, and to not render “aid or assistance” to maintaining the situation (II).The EU and its member states are, therefore, under the obligation to cease all economic relations with Israeli entities which could contribute to maintaining the illegal situation arising from settlements, including the importation of goods. (III). The modalities for the application of the obligation to prohibit, in the EU, the trade of goods from Israeli settlements will be analysed, and in particular, with respect to EU and WTO law (IV).Lastly, the paper will analyse the scope of States’ obligation to adopt measures for business entities registered on their soil which are aimed at inducing them to refrain from any economic activity that can contribute to perpetuating settlements (V).