58. The Court is also of the view that the optional nature of the declaration and its unilateral character stem from the international law principle of state sovereignty. As far as unilateral acts are concerned, state sovereignty commands that states are free to commit themselves and that they retain discretion to withdraw their commitments. 59. As a consequence, the Court holds that the Respondent is entitled to withdraw its declaration pursuant to Article 34(6) and that such withdrawal is valid under the Protocol.