States — Head of State — Privileges and immunities — Status when visiting territory of another State — Obligations of the host State — Member States of the European Union — Citizenship of the European Union — Free movement of EU citizens — Whether applicable to Head of State — Head of State of one EU Member State barred from entering the territory of another EU Member State — Whether compatible with EU law

Relationship of international law and municipal law — Effect of international law in the law of the European Union — International law forming part of the EU legal order — International law regarding Heads of State — The law of the European Union