PART III.

OBSERVANCE, APPLICATION AND INTERPRETATION OF TREATIES

SECTION 1. 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.

【observance    noun

1 an act or instance of following, obeying, or conforming to:

the observance of traffic laws.

2 a keeping or celebration by appropriate procedure, ceremonies, etc.:

the observance of the Sabbath.

3 a procedure, ceremony, or rite, as for a particular occasion:

patriotic observances.

4 a rule or custom to be followed or obeyed; a customary practice.

5 Roman Catholic Church.

a rule or discipline for a religious house or order.

a house or order observing a rule or discipline.

6 an act or instance of watching, noting, or perceiving; observation.】

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.