Article 4 of Decision No 1/95 of the EC-Turkey Association Council of 22 December 1995 on implementing the final phase of the Customs Union must be interpreted as meaning that a tax on motor vehicles such as that at issue in the main proceedings, which must be paid by persons operating heavy goods vehicles registered in Turkey and in transit through Hungarian territory, constitutes a charge having equivalent effect to a customs duty within the meaning of that article.

Accordingly, it should be noted that any pecuniary charge, however small and whatever its designation and mode of application, which is imposed unilaterally on goods by reason of the fact that they cross a frontier, and which is not a customs duty in the strict sense, constitutes a charge having equivalent effect within the meaning of Articles 28 and 30 TFEU (judgments of 18 January 2007, Brzeziński, C‑313/05, EU:C:2007:33, paragraph 22 and the case-law cited, and of 2 October 2014, Orgacom,C‑254/13, EU:C:2014:2251, paragraph 23). The justification for the prohibition of charges having an effect equivalent to customs duties lies in the fact that those charges constitute an obstacle to the movement of goods, in that they artificially increase the price of imported or exported goods in relation to domestic products (judgment of 21 March 1991, Commission v Italy, C‑209/89, EU:C:1991:139, paragraph 7).

In addition, charges having equivalent effect to customs duties are prohibited irrespective of the purpose for which they were introduced and the destination of the revenue they generate (judgment of 21 June 2007, Commission v Italy, C‑173/05, EU:C:2007:362, paragraph 42 and the case-law cited).

Moreover, the Customs Union necessarily entails the free movement of goods between the Member States. That freedom could not itself be complete if it were possible for the Member States to impede or interfere in any way with the movement of goods in transit. It is thereof necessary, as a consequence of the Customs Union and in the mutual interest of the Member States, to acknowledge the existence of a general principle of freedom of transit of goods within the European Union (judgment of 21 June 2007, Commission v Italy, C‑173/05, EU:C:2007:362, paragraph 31 and the case-law cited). Indeed, the Member States would contravene that principle if they were to apply to goods in transit through their territory transit duties or other charges imposed in respect of transit (judgment of 16 March 1983, SIOT, 266/81, EU:C:1983:77, paragraph 19).

It must also be observed that the Court has previously held that a charge which is triggered by the carriage of goods and which is imposed not on a product as such, but on a necessary activity in connection with the product, may fall within the scope of Article 30 TFEU (judgment of 17 July 2008, Essent Netwerk Noord and Others, C‑206/06, EU:C:2008:413, paragraph 44 and the case-law cited). Indeed, such a charge is imposed on products, even where it has been levied on the transport of goods or the use of roads and has first to be paid by the person operating the heavy goods vehicle (see, to that effect, judgment of 17 July 1997, Haahr Petroleum, C‑90/94, EU:C:1997:368, paragraph 38).

Accordingly, the Court finds that, in the light of the case-law cited in paragraphs 40 to 43 above, even though the motor vehicle tax is not levied on products as such, it is imposed on the goods transported by vehicles registered in a third country, in particular Turkey, when they cross the Hungarian border, and not, as submitted by the Hungarian and Italian Governments, on the transport service.

(see paras 39, 40, 42, 43, 46, 49, operative part)