With the pretext of the global ‘war on terror’, States have repatriated a notable number of individuals who are considered threats to the public safety of the host country. Expulsion orders have often been issued on the basis of Memoranda of Understanding (MoUs)—written accords that enumerate a long list of undertakings dictating guarantees for the fair and human treatment of returnees. This paper aims to investigate whether the implementation of diplomatic assurances, whether formalized or not within MoUs, can undermine core refugee rights. Through a detailed review of international human rights case law, it observes that the text of MoUs per se does not seem to raise issues of incompatibility with refugee rights. However, the actual negotiation of individualized diplomatic assurances in concrete situations can hamper refugees' ‘access to protection’, here understood as the combination of non-refoulement, and the right to access fair asylum procedures and effective remedies before removal.