Myanmar and Uruguay are currently the only countries in the world that deny immigrants any path to naturalization. Uruguayan legal citizenship has special characteristics. A person who acquires it retains their nationality of origin, which is determined by Uruguayan law to be that of their country of birth and therefore, is immutable. Legal citizens acquire political rights but do not acquire Uruguayan nationality as natural citizens do. According to Uruguayan law, those born in Uruguay or whose parents or grandparents are Uruguayan natural citizens are considered to be Uruguayan nationals.
The Uruguayan State defined nationality in this way based on an interpretation of the Constitution made by the jurist Justino Jiménez de Aréchaga in the mid-twentieth century. Jiménez de Aréchaga's interpretation, found in one of Uruguay's fundamental academic interpretative texts, states: "In the first place, nationality is presented to us as a natural bond, derived from birth, from blood". Likewise, this jurist believed that "nationality corresponds to a certain sociological or psychological reality". Speaking on behalf of the drafters of the Constitution of 1830, this jurist concluded: "The quality of nationality thus depends on one fact: birth in the territory of the State". Finally, "nationality is irrevocable".
According to Uruguayan law, the concepts of nationality and citizenship are distinguishable, the first being of a real or sociological nature and the second of a legal nature.
He argued that nationality and citizenship are two completely different individual conditions. According to Aréchaga's view nationality is a permanent state of the individual, which does not suffer any alteration whatever the point of the earth they inhabit, and citizenship is, on the contrary, variable and alters with the different domiciles that men acquire in the different societies into which mankind is divided.
The source of citizenship, he added, is in the actual domicile and not in nationality.
Therefore, he says: "each state feels who its nationals are, and declares it by its law; on the other hand, each state decides who its citizens are, and it disposes of them by its law, for nationality corresponds to a certain sociological or psychological reality." (JUSTINO JIMÉNEZ DE ARECHAGA, La Constitución Nacional. Volume II pg. 186)
As a result of Uruguay's unusual distinction between citizenship and nationality (it's the only country in the world that recognizes the right to citizenship without being a national), legal citizens have encountered problems with their Uruguayan passports at airports around the world since 2015. This is due to recommendations in the seventh edition of Doc. 9303 of the International Civil Aviation Organization (ICAO), which requires that travel documents issued by participating states include the "Nationality" field. The lack of a naturalization path means that the Nationality field in legal citizens' passports indicates their country of birth, which Uruguay assumes to be their nationality of origin. Many countries do not accept passports issued by a country that declares the holder to be a national of another country. As a consequence, it has severely curtailed legal citizens' exercise of the right to free movement, as their travel abroad is often difficult or downright impossible.
Due to its current and narrow definition of nationality, Uruguay could be violating the sovereignty of other countries by assigning foreign nationalities in its official documents, thus overriding their powers. Some Uruguayan legal citizens may even, as a result of the application of a national law of a third nation and this Uruguayan interpretation, become de facto stateless.