GATT/WTO
National treatment is an integral part of many World Trade Organization agreements. Together with the Most-Favoured-Nation principle, national treatment is one of the cornerstones of WTO trade law. It is found in all 3 of the main WTO agreements (GATT, GATS and TRIPS).
National treatment is a basic principle of GATT/WTO that prohibits discrimination between imported and domestically produced goods with respect to internal taxation or other government regulation. The principle of national treatment is formulated in Article 3 of the GATT 1947 (and incorporated by reference in GATT 1994); Article 17 of the General Agreement on Trade in Services (GATS); and in Article 3 of the Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS). The aim of this trade rule is to prevent internal taxes or other regulations from being used as a substitute for tariff protection.
A good summary is found in Japan-Alcohol which states; " national treatment obligation is a general prohibition on the use of internal taxes and other internal regulatory measures so as to afford protection to domestic production".
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