Pacem in Terris §25

²⁵ Again, every human being has the right to freedom of movement and of residence within the confines of his own State. When there are just reasons in favor of it, he must be permitted to emigrate to other countries and take up residence there.(22) The fact that he is a citizen of a particular State does not deprive him of membership in the human family, nor of citizenship in that universal society, the common, world-wide fellowship of men.