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In order to prevent discriminatory practices and to assure equality of treatment, both Contracting Parties agree that:
(a) Each of the Contracting Parties may impose or permit to be imposed just and reasonable charges for the use of public airports, and other facilities. Each of the Contracting Parties agrees, however, that these charges shall not be higher than would be paid for the use of such airports and facilities by its national aircraft engaged in similar international services.
(b) Fuel, lubricating oils and spare parts introduced into or taken on board aircraft in the territory of one Contracting Party by the other Contracting Party or its nationals, and intended solely for use by aircraft of the airlines of such Contracting Party, shall, with respect to the imposition of customs duties, inspection fees or other national duties or charges by the Contracting Party whose territory is entered, be accorded the same treatment as that applying to national airlines and to airlines of the most favored nation.
(c) The fuel, lubricating oils, spare parts, regular equipment and aircraft stores retained on board civil aircraft of the airlines of one Contracting Party authorized to operate the routes and services described in the Annex shall, upon arriving in or leaving the territory of the other Contracting Party, be exempt from customs duties, inspection fees or similar duties or charges, even though such supplies be used or consumed by such aircraft on flights in that territory.
(d) Goods so exempted, may only be unloaded with the approval of the customs authorities of the other Contracting Party. These goods which are to be re-exported shall be kept until re-exportation under customs-supervision.