Where a consignment is made up of goods falling within different tariff subheadings, and dealing with each of those goods in accordance with its tariff subheading for the purpose of drawing-up the customs declaration would entail a burden of work and expense disproportionate to the import or export duty chargeable, the customs authorities may, upon application by the declarant, agree that import or export duty be charged on the whole consignment on the basis of the tariff subheading of the goods which are subject to the highest rate of import or export duty.
Customs authorities shall refuse the use of the simplification referred to in paragraph 1 to goods subject to prohibitions or restrictions or excise duty where the correct classification is necessary to apply the measure.