1980 United Nations — Treaty Series • Nations Unies — Recueil des Traités 339 2. Unless the treaty otherwise provides or the negotiating States have other wise agreed, the provisional application of a treaty or a part of a treaty with respect to a State shall be terminated if that State notifies the other States between which the treaty is being applied provisionally of its intention not to become a party to the treaty. PART m. OBSERVANCE, APPLICATION AND INTERPRETATION OF TREATIES SECTION i. OBSERVANCE OF TREATIES Article 26. "PACTA SUNT SERVANDA" Every treaty in force is binding upon the parties to it and must be performed by them in good faith. Article 27. INTERNAL LAW AND OBSERVANCE OF TREATIES A party may not invoke the provisions of its internal law as justification for its failure to perform a treaty. This rule is without prejudice to article 46. SECTION 2. APPLICATION OF TREATIES Article 28. NON-RETROACTIVITY OF TREATIES Unless a different intention appears from the treaty or is otherwise established, its provisions do not bind a party in relation to any act or fact which took place or any situation which ceased to exist before the date of the entry into force of the treaty with respect to that party. Article 29. TERRITORIAL SCOPE OF TREATIES Unless a different intention appears from the treaty or is otherwise established, a treaty is binding upon each party in respect of its entire territory. Article 30. APPLICATION OF SUCCESSIVE TREATIES RELATING TO THE SAME SUBJECT-MATTER 1. Subject to Article 103 of the Charter of the United Nations, the rights and obligations of States parties to successive treaties relating to the same subject-matter shall be determined in accordance with the following paragraphs. 2. When a treaty specifies that it is subject to, or that it is not to be considered as incompatible with, an earlier or later treaty, the provisions of that other treaty prevail. 3. When all the parties to the earlier treaty are parties also to the later treaty but the earlier treaty is not terminated or suspended in operation under article 59, the earlier treaty applies only to the extent that its provisions are compatible with those of the later treaty. 4. When the parties to the later treaty do not include all the parties to the earlier one: (a) As between States parties to both treaties the same rule applies as in paragraph 3; (o) As between a State party to both treaties and a State party to only one of the treaties, the treaty to which both States are parties governs their mutual rights and obligations. 5. Paragraph 4 is without prejudice to article 41, or to any question of the ter mination or suspension of the operation of a treaty under article 60 or to any quesVol. 1155,1-18232