The EU Emergency Trust Fund for Africa was created in 2015 to alleviate migratory pressures resulting from crisis situations in Africa. However, the crisis in Africa was largely a construct of the EU, which in 2015 faced pressure from Member States to react to increased migration flows to Europe. Drawing on the (de)politicisation literature and 23 original expert interviews, we show that the creation of the EUTF enabled the Commission to depoliticise the ‘refugee crisis’ by reframing migration as a technocratic problem requiring the use of development aid to address its root causes in Africa. This approach, however, reintroduced strategic considerations at the heart of development aid, evidencing a horizontal transfer of politicisation from the migration policy domain to the development policy area. Our findings extend recent debates on the internal-external nexus in EU policymaking by revealing how political constraints and blockages in the internal dimension motivate EU external engagement. We also contribute to the strategic politicisation management literature by highlighting the role of three facilitating (or inhibiting) factors behind the success (or failure) of (de)politicisation strategies, namely, the type of actors involved, the locale where the policy is implemented, and the salience and polarisation of the policy-domains involved.