Southern African Development Community 4. Where an existing agreement is inconsistent with the principles and objectives of this Protocol, the Member State shall take steps to amend the agreement accordingly. ARTICLE 16 SIGNATURE This Protocol shall be signed by duly authorized representatives of the Member States. ARTICLE 17 RATIFICATION This Protocol shall be subject to ratification by the Signatories in accordance with their respective constitutional procedures. ARTICLE 18 ACCESSION This Protocol shall remain open for accession by any Member State. ARTICLE 19 AMENDMENTS 1. Any State Party may propose an amendment to this Protocol. Protocol on Politics, Defence and Security Co-operation 16