sofia bulgaria parliament speaker dimitar glavchev resign friday move say avoid political upheaval country prepare take six-month rotate european union presidency january opposition socialists demand glavchev resignation say would boycott parliament sessions step ban leader kornelia ninova chamber call offences deputies members government wednesday glavchev describe resignation moral act say intention restore calm parliament cast shadow bulgaria eu presidency always say state stability important anything say prime minister boyko borissov parliament vote appoint tsveta karayancheva senior member rule center-right gerb party replace glavchev glavchev make mistake resignation preventative measure lead parliamentary crisis fall government daniel smilov analyst bulgaria centre liberal strategies tell reuters gerb try complicate situation center-right gerb lead borissov return power third term since 2009 snap election march coalition government one-seat majority also support small populist party bulgaria 's parliament speaker resign 'to avoid political upheaval