In 2006, the
International Law Commission adopted draft Articles on Diplomatic Protection, largely codifying established practice, which in general reaffirmed the rule. However it sought to ease the strictness of traditional practice with a proposal that where the nationality of a protecting state is "predominant", diplomatic protection may be given. These draft Articles have not been submitted to a conference to formalize them into a treaty. The draft Article 7 states: Eileen Denza, Professor of International Law at
University College London and a former Legal Adviser in the
Foreign and Commonwealth Office, states that the rule is a codification of a "classic rule", and as of 2018, remains "modern state practice" internationally. James Larry Taulbee and Gerhard von Glahn, in their 2022 U.S. legal textbook, write that regarding the underlying Articles 3 to 6 of the Convention on Certain Questions Relating to the Conflict of Nationality: "states today in practice follow almost all of those provisions, despite the absence of general conventional rules." They do not use the name "Master Nationality Rule", but explicitly give a summary of the rule.
Cold War exceptions During the
Cold War era, the United States signed consular agreements with certain
Warsaw Pact countries providing that a U.S. citizen who entered that country with a U.S.
passport and the appropriate
visa would not be subsequently treated as a citizen of that country (and hence prevented from leaving). The Warsaw Pact countries involved (notably Poland) wished to encourage
tourism from emigrants and their descendants settled in the U.S. Since the dissolution of the Warsaw Pact in 1991, many of those countries have abolished visa requirements for U.S. citizens thus nullifying those provisions (for detailed discussion see under
Dual citizenship in Poland). Australia, Canada, and the United States have concluded similar consular agreements with the People's Republic of China. ==Detailed explanation by the United Kingdom==