Western powers prepared to pile sanctions on Belarus and cut off its aviation links on Monday, furious after it scrambled a warplane to intercept a Ryanair aircraft and arrest a dissident journalist, an act one leader denounced as 'state piracy'.

In a video posted online, the detained blogger Roman Protasevich, 26, said he was in good health, being held in a pretrial detention facility in Minsk, and acknowledged having played a role in organising mass disturbances in the capital last year...