Treaties — Spain-United Kingdom Air Services Agreement, 1950 — Spanish Government deleting proposed new British Airways flights from schedule — Countermeasures by United Kingdom Secretary of State — Whether acting in breach of treaty — Article 59(1) of Air Navigation Order 1980 — Whether Secretary of State justified in varying applicants’ operating permission — Applicants seeking judicial review

Relationship of international law and municipal law — Treaties — Implementation — Effect in municipal courts — Alleged breach of treaty by Spanish Government — Whether municipal court entitled to construe treaty — Whether treaty confined in its effect to international sphere — Whether incorporation of treaty into municipal law necessary — The law of England