State immunity — Jurisdictional immunity — Consular employee — Citizen of receiving State employed as commercial officer — Contract of employment — Termination — Claim for unlawful dismissal — Whether foreign State entitled to jurisdictional immunity — Whether employee integrated into organizational structure of foreign State — Whether enquiry by municipal courts into lawfulness of dismissal would infringe sovereignty of foreign State

Consular relations — Consular employee — Commercial officer — Whether performing consular functions — Vienna Convention on Consular Relations, 1963, Article 5

Relationship of international law and municipal law — Rules of customary international law — Compatibility of rules on State immunity with principles of Italian Constitution — Incorporation of rules of customary international law into municipal law — Article 10 of Constitution — The law of Italy