Claude Béglé, chairman of the board of directors at Switzerland’s post office, has resigned with immediate effect.
It follows mounting media criticism of his management style.
Three other senior figures in the government-owned group have left over differences with 61-year-old Béglé in the past two months.
In a statement on Tuesday evening, the chairman said long-running and rancorous debates over strategy, personal attacks and public defamation had contributed to his decision to quit.
He follows board member Rolf Hug, who stepped down on December 22, former chief executive Michel Kunz, who was replaced eight days before that and Wolfgang Werlé, a director who quit on January 6.
Communications Minister Moritz Leuenberger, who has accepted the resignation, had been informed on Friday of Béglé’s discussions with the Post to quit. The decision was announced on Tuesday evening.
Cabinet will discuss the issue when it meets on Wednesday.
swissinfo.ch and agencies