Article 29 (4)

Each Contracting Party shall endeavour not to increase any customs duty or charge of any kind imposed on or in connection with importation or exportation:

(a) in the case of the importation of Energy Materials and Products listed in Annex EM I or Energy-Related Equipment listed in Annex EQ I and described in Part I of the Schedule relating to the Contracting Party referred to in article II of the GATT 1994, above the level set forth in that Schedule, if the Contracting Party is a member of the WTO;

(b) in the case of the exportation of Energy Materials and Products listed in Annex EM I or Energy-Related Equipment listed in Annex EQ I, and that of their importation if the Contracting Party is not a member of the WTO, above the level most recently notified to the Secretariat, except as permitted by the provisions made applicable by subparagraph (2)(a).