PULP MILLS (JUDGMENT) 67 cle 8 [180 days], the other party may carry out or authorize the work planned”. 144. Consequently, in the opinion of the Court, as long as the procedural mechanism for co-operation between the parties to prevent significant damage to one of them is taking its course, the State initiating the planned activity is obliged not to authorize such work and, a fortiori, not to carry it out. 145. The Court notes, moreover, that the 1975 Statute is perfectly in keeping with the requirements of international law on the subject, since the mechanism for co-operation between States is governed by the principle of good faith. Indeed, according to customary international law, as reflected in Article 26 of the 1969 Vienna Convention on the Law of Treaties, “[e]very treaty in force is binding upon the parties to it and must be performed by them in good faith”. That applies to all obligations established by a treaty, including procedural obligations which are essential to co-operation between States. The Court recalled in the cases concerning Nuclear Tests (Australia v. France) (New Zealand v. France): “One of the basic principles governing the creation and performance of legal obligations, whatever their source, is the principle of good faith. Trust and confidence are inherent in international co-operation . . .” (Judgments, I.C.J. Reports 1974, p. 268, para. 46, and p. 473, para. 49 ; see also Border and Transborder Armed Actions (Nicaragua v. Honduras), Jurisdiction and Admissibility, Judgment, I.C.J. Reports 1988, p. 105, para. 94.) 146. The Court has also had occasion to draw attention to the characteristics of the obligation to negotiate and to the conduct which this imposes on the States concerned : “[the Parties] are under an obligation so to conduct themselves that the negotiations are meaningful” (North Sea Continental Shelf (Federal Republic of Germany/Denmark ; Federal Republic of Germany/Netherlands), Judgment, I.C.J. Reports 1969, p. 47, para. 85). 147. In the view of the Court, there would be no point to the co-operation mechanism provided for by Articles 7 to 12 of the 1975 Statute if the party initiating the planned activity were to authorize or implement it without waiting for that mechanism to be brought to a conclusion. Indeed, if that were the case, the negotiations between the parties would no longer have any purpose. 148. In this respect, contrary to what Uruguay claims, the preliminary work on the pulp mills on sites approved by Uruguay alone does not constitute an exception. This work does in fact form an integral part of the construction of the planned mills (see paragraphs 39 and 42 above). 149. The Court concludes from the above that the agreement to set up the GTAN did not permit Uruguay to derogate from its obligations of information and notification under Article 7 of the 1975 Statute, and that by authorizing the construction of the mills and the port terminal at 57