Diplomatic and consular intercourse and privileges — Permanent diplomatic envoys — Privileges and immunities — The retinue of diplomatic envoys — Categories of persons entitled to diplomatic immunity — Whether embassy driver entitled to immunity — Whether insurers of embassy vehicle entitled to rely on diplomatic immunity — Waiver — Whether agreement to provide insurance cover constitutes waiver by the insurer of right to rely on the immunity of his insured — Onus of proving entitlement to immunity — The law of Belgium