Decision of the Supreme Court of Justice of the Nation, delivered 14 November 2006 in the case “National Parks Administration v. Neuquén Province about Declaratory action of unconstitutionality. The National Parks Administration filed a declaratory action so that the Province of Neuquén is ordered to cease any action which may imply a violation of the powers conferred by Law 22351 (National Parks – Declaration of Reserves) and an interference with the powers of the national authorities, according to sections 31 and 75, subsection 30, of the National Constitution. It claimed that, among other actions, the Minister of Production and Tourism of the Province of Neuquén sent a notification letter to the Director of the National Park “Laguna Blanca” requiring him not to execute any action authorizing fishing in that park, which was rejected arguing the lack of jurisdiction of the province, and imposed penalties for fishing in waters located within the Park and during closed seasons. Due to the above-mentioned reasons, the petitioner concluded that the action adopted by the Province of Neuquén violated the distribution of constitutional jurisdictions in environmental matters. Likewise, it requested a precautionary measure until the issuance of a final decision on the case, with the purpose of instructing the defendant not to execute administrative actions, enforce rules and/or impose penalties to those who infringe the provisions of the provincial legislation in territories under federal jurisdiction. The Supreme Court, by majority, declared to have original jurisdiction in the case and dismissed the requested precautionary measure. It instructed to serve notice of the filed claim to the Province of Neuquén, in order to proceed according to the ordinary rules.