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.
Vehicle registration plates of Sweden any country acronym e.g. American diplomats don't have US as their first two letters. They're ordered by the sovereign states' name in the French language. Thus AA denotes South Africa (i.e. Afrique du Sud). AB denotes Albania (i.e. Albanie) and so forth up until DT. The three digits are just a serial number. The last letter shows what kind of task the diplomat has. The approval sticker was placed last on the right. Just like the personal plates these vehicles have a standard format registration as well, which means a re-registration is not needed if the vehicle changes owner. Taxi