State immunity — Jurisdictional immunity — Immunity of individual officials — Head of State immunity — Immunity ratione personae and immunity ratione materiae — Immunity ratione personae confined to Head of State and certain high-ranking officials — Immunity ratione materiae applicable only in respect of official acts — Vienna Convention on Diplomatic Relations, 1961 — Vice-President of State accused of misappropriation of funds and money laundering by authorities of another State — Whether entitled to immunity — Immunity of diplomatic agents — State sovereignty — Customary international law — The law of France