Ali Mahmoud Hassan Mohammed (Dr Mahmoud) v. Abdulmagid Breish (Mr Breish), Hussein Mohamed Hussein Abdlmora (Dr Hussein), Mark James Shaw and Shane Michael Crooks (Receiver), the Libyan Investment Authority, Mohsen Derregia (Dr Derregia)

Governments — Status of government — Recognition — Whether particular entity to be treated as the government of a State — Role of national courts — Recognition a matter for the executive — Whether national court entitled to entertain challenge to the constitutional validity of foreign government’s acts — Nature of challenge — Whether upholding challenge would require court to inquire into status of foreign government — Libya — Revolution in 2011 — Existence of competing regimes — Whether United Kingdom Government had recognized one entity as the Government of Libya Recognition — Governments — United Kingdom policy — April 1980 Statement that United Kingdom Government would no longer make formal statements regarding recognition of foreign governments — Whether precluding statement of recognition in all circumstances — Evidence of recognition — Letters from Foreign and Commonwealth Office — Whether indicating unequivocal recognition — Libya — Competing regimes Relationship of international law and municipal law — Whether entity the government of a foreign State — Whether determination of that issue a matter for courts or government — Effect of unequivocal recognition by government of forum State — Whether courts entitled to call such recognition into question — Separation of powers — Difference from doctrines of act of State, sovereign immunity and non-justiciability — The law of England