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Without prejudice to the provisions of the second paragraph of Article 8, disputes which may arise between Contracting States as to the interpretation or the application of the present Statute shall be settled in the following manner:
Should it prove impossible to settle such dispute either directly between the Parties or by any other method of amicable settlement, the Parties to the dispute may, before resorting to any procedure of arbitration or to a judicial settlement, submit the dispute for an advisory opinion to the body established by the League of Nations as the advisory and technical organisation of Members of the League for matters of communications and transit. In urgent cases a preliminary opinion may be given recommending temporary measures, including measures to restore the facilities for international traffic which existed before the act or occurrence which gave rise to the dispute.
Should it prove impossible to settle the dispute by any of the methods of procedure enumerated in the preceding paragraph, the Contracting States shall submit their dispute to arbitration, unless they have decided or shall decide, under an agreement between them, to bring it before the Permanent Court of International Justice.