State immunity — Attachment and execution — Embassy bank account — Judgment creditor seeking to levy execution against foreign State by attachment of bank account — Principles of international law governing immunity of embassy funds from enforcement jurisdiction of receiving State — Whether execution permissible only if account used exclusively for non-sovereign purposes — Assets used for exclusively commercial purposes — Requirement of ministerial authorization for execution — Italian Law No 1263 of 1926

Diplomatic relations — Immunity — Embassy bank account — Account in use for meeting expenses of embassy — Whether subject to execution in receiving State — Vienna Convention on Diplomatic Relations, 1961 — Provisions applicable only to diplomatic envoys and not to States

Relationship of international law and municipal law — Customary international law — Automatic incorporation into municipal law — Italian Constitution, Article 10 — The law of Italy