Article 17

1. The provisions of Articles 9 to 15(1) shall also apply to customs duties of a fiscal  nature. Such duties shall not, however, be taken into consideration for the purpose of  calculating either total customs receipts or the reduction of customs duties as a  whole as referred to in Article 14( 3 ) and ( 4 ).

Such duties shall; at each reduction, be lowered by not less than 10% of the basic  duty. Member States may reduce such duties more rapidly than is provided for in  Article 14.

2. Member States shall, before the end of the first year after the entry into force of this Treaty, inform the Commission of their customs duties of a fiscal nature.

3. Member States shall retain the right to substitute for these duties an internal tax which complies with the provisions of Article 95.

4. If the Commission finds that substitution for any customs duty of a fiscal nature meets with serious difficulties in a Member State, it shall authorize that State to retain the duty on condition that it shall abolish it not later than six years after the  entry into force of this Treaty. Such authorization must be applied for before the end of the first year after the entry into force of this Treaty.

Section 2

Setting up of the Common Customs Tariff

Article 18

The Member States declare their readiness to contribute to the development of  international trade and the lowering of barriers to trade by entering into agreements  designed, on a basis of reciprocity and mutual advantage, to reduce customs duties  below the general level of which they could avail themselves as a result of the  establishment of a customs union between them.

Article 19

1. Subject to the conditions and within the limits provided for hereinafter, duties in  the Common Customs Tariff shall be at the level of the arithmetical average of the  duties applied in the four customs territories comprised in the Community.

2. The duties taken as the basis for calculating this average shall be those applied by  Member States on 1 January 1957.

In the case of the Italian tariff, however, the duty applied shall be that without the  temporary 10% reduction. Furthermore, with respect to items on which the Italian  tariff contains a conventional duty, this duty shall be substituted for the duty applied  as defined above, provided that it does not exceed the latter by more than 10%. Where the conventional duty exceeds the duty applied as defined above by more than  10%, the latter duty plus 10% shall be taken as the basis for calculating the  arithmetical average.

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