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The Contracting States shall publish promptly all regulations relating to Customs and similar formalities and all modifications therein, which have not been already published, in such a manner as to enable persons concerned to become acquainted with them and to avoid the prejudice which might result from the application of Customs formalities of which they are ignorant.
The Contracting States agree that no Customs regulations shall be enforced before such regulations have been published, either in the Official Journal of the country concerned or through some other suitable official or private channel of publicity.
This obligation to publish in advance extends to all matters affecting tariffs and import and export prohibitions or restrictions.
In cases, however, of an exceptional nature, when previous publication would be likely to injure the essential interests of the country, the provisions of the second and third paragraphs of this Article will lose their obligatory force. In such cases, however, publication shall, so far as possible, take place simultaneously with the enforcement of the measure in question.