348 United Nations — Treaty Series • Nations Unies — Recueil des Traités 1980 4. Nothing in the foregoing paragraphs shall affect the rights or obligations of the parties under any provisions in force binding the parties with regard to the settle ment of disputes. 5. Without prejudice to article 45, the fact that a State has not previously made the notification prescribed in paragraph 1 shall not prevent it from making such notification in answer to another party claiming performance of the treaty or alleging its violation. Article 66, PROCEDURES FOR JUDICIAL SETTLEMENT, ARBITRATION AND CONCILIATION If, under paragraph 3 of article 65, no solution has been reached within a period of twelve months following the date on which the objection was raised, the following procedures shall be followed: (a) Any one of the parties to a dispute concerning the application or the interpreta tion of article 53 or 64 may, by a written application, submit it to the Interna tional Court of Justice for a decision unless the parties by common consent agree to submit the dispute to arbitration; (b) Any one of the parties to a dispute concerning the application or the interpreta tion of any of the other articles in Part V of the present Convention may set in motion the procedure specified in the Annex to the Convention by submitting a request to that effect to the Secretary-General of the United Nations. Article 67. INSTRUMENTS FOR DECLARING INVALID, TERMINATING, WITHDRAWING FROM OR SUSPENDING THE OPERATION OF A TREATY 1. The notification provided for under article 65, paragraph 1 must be made in writing. 2. Any act declaring invalid, terminating, withdrawing from or suspending the operation of a treaty pursuant to the provisions of the treaty or of paragraphs 2 or 3 of article 65 shall be carried out through an instrument communicated to the other parties. If the instrument is not signed by the Head of State, Head of Government or Minister for Foreign Affairs, the representative of the State communicating it may be called upon to produce full powers. Article 68. REVOCATION OF NOTIFICATIONS AND INSTRUMENTS PROVIDED FOR IN ARTICLES 65 AND 67 A notification or instrument provided for in article 65 or 67 may be revoked at any time before it takes effect. SECTION 5. CONSEQUENCES OF THE INVALIDITY, TERMINATION OR SUSPENSION OF THE OPERATION OF A TREATY Article 69. CONSEQUENCES OF THE INVALIDITY OF A TREATY 1. A treaty the invalidity of which is established under the present Convention is void. The provisions of a void treaty have no legal force. 2. If acts have nevertheless been performed in reliance on such a treaty: (a) Each party may require any other party to establish as far as possible in their mutual relations the position that would have existed if the acts had not been performed; (b) Acts performed in good faith before the invalidity was invoked are not rendered unlawful by reason only of the invalidity of the treaty. Vol. 1155,1-18232