International vehicle registration code registration plate. When the distinguishing sign is incorporated in the registration plate, it must also appear on the front registration plate of the vehicle. The requirement to display a separate distinguishing sign is not necessary within the European Economic Area, for vehicles with license plates in the common EU format which satisfy the requirements of the Vienna Convention, and so are also valid in non-EU countries signatory to the convention. Separate signs are also not needed for Canada, Mexico and the United States, where the province, state or district of registration is usually embossed or surface-printed on the vehicle registration
International vehicle registration code system is used for vehicles belonging to the diplomats of foreign countries with license plate from the host country. That system is host country-specific and varies largely from country to country. For example TR on a diplomatic car in the USA indicates Italian, not Turkish. Such markings in Norway are indicated with numbers only, again different from international standards (e.g. 90 means Slovakian. International vehicle registration code The country in which a motor vehicle's vehicle registration plate was issued may be indicated by an international licence plate country code, formerly known as an International Registration Letter or International Circulation Mark.