The Pope, as a spiritual and temporal leader, wields a double sovereignty: over the City of the Vatican as Head of State, and over the Holy See (or Apostolic See) as Head of the Roman Catholic Church. This fundamental distinction, perennialized by the 1929 Latran accords, is at the basis of the papal foreign policy: although it is sometimes designed as the emanation of the Vatican's national sovereignty, it is generally carried out in the name of the Holy See (the religious authority).
[...] Although the Vatican itself is a active member State of some IOs like the Universal Postal Union, the Holy See generally has an observer status and does not take part in voting procedures. Papal emissaries participate in almost every international conference, and often play an important role in the debates. Even though the opinion of the Apostolic See is often sought by other countries to cast an impartial light on matters in discussion, some nations regularly protest against the weight given to the Catholic Church compared to other religions. [...]
[...] as nuncios though they do not head the diplomatic corps in the country to which they are accredited. Apostolic delegates: Archbishops who represent the Pope only to the local Church because the Holy See does not have diplomatic relations with that particular country. Chargés d'affaires: They head the corps in the absence of a nuncio or an apostolic delegate. Representation in States: Under the pontificate of John Paul II, The Holy See's diplomatic representations almost doubled in number, going from 89 to172 nunciatures or delegations, the second largest diplomatic network after the United States. [...]
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