International agreements such as the Treaty Establishing Energy Community (TEEC) in South East Europe serve as agents for enforcement of the EU State aid acquis within broader international law. Aside from the legal aspects of the Case ECS-10/18 involving a guarantee for the construction of a coal power plant in Bosnia and Herzegovina, the analysis shows the equal importance of State aid related economic analysis for aid providers, beneficiaries as well as enforcement institutions under TEEC. Ministerial Council’s Advisory Committee, as the highest decision-making body, sent the message of the importance of prior economic assessments to both sides in the dispute.