Comity — Nature of comity — Effect on the jurisdiction of national courts — Principle of non-justiciability of sovereign acts of foreign States — Whether based upon comity — Foreign State's bank notes held by commercial bank in the United Kingdom — Allegation that bank notes printed on paper subject to United Kingdom patent — Action for alleged violation of patent — Whether contrary to comity for English courts to entertain action

Economics, trade and finance — Currency — Issue of currency by State a sovereign act — Disposal of bank notes in territory of another State — Bank notes not legal tender in State in which they were disposed — Foreign currency treated as commodity

Relationship of international law and municipal law — Act of State and non-justiciability — Principle that English courts will not adjudicate upon acts of foreign States — Principle limited to acts of a sovereign character performed within the territory of the foreign State — Issue of currency — Disposal in the United Kingdom of bank notes issued by foreign State

State immunity — Jurisdictional immunity — Relationship between State immunity and principles of non-justiciability — The law of England