State immunity — Jurisdictional immunity — Commercial activity — Agreement for construction of railway line — Whether commercial — Waiver — Arbitration — Whether signature of arbitration clause constitutes waiver of jurisdictional immunity — Whether waiver extending to proceedings instituted to obtain exequatur for arbitral award

State immunity — Attachment and execution — Debts owed to foreign State for overflight of territory by commercial aircraft — Whether liable to attachment to enforce payment of arbitral award against foreign State — Whether such debts result from State's exercise of sovereign powers

Arbitration — Arbitration between company and foreign State — Award — Binding force of award — Burden of proof — New York Convention on the Recognition and Enforcement of Foreign Arbitral Awards, 1958 — Enforcement — Whether signature of arbitration clause constitutes waiver of jurisdictional immunity for proceedings before municipal courts instituted to obtain exequatur for award

Arbitration — Procedure — Powers of arbitrators — Interpretation of treaties — Whether arbitrators empowered to interpret inter-State treaty affecting private interests of parties to arbitration — Whether arbitrators bound by government interpretation of treaty

Treaties — Application — By arbitral tribunal — Clear text — Interpretation — Agencies of interpretation — Arbitral tribunal — Circumstances in which arbitral tribunal empowered to interpret treaties — Whether arbitrators bound by government interpretation

Claims — State control over private claims — Effects of inter-State agreement settling claim on rights of private claimant

Economics, trade and finance — State contracts — Arbitration — Award — Recognition and enforcement — The law of France