Arendt, who served on the SEW committee for 25 years and held the position of president for 12, said he would also be relinquishing his roles at the OGBL and FGIL unions.
In a statement, he said he regretted that leading voices in secondary education did not respect minimum standards for constructive cooperation and respectful conduct.
Arendt also alluded to a “toxic atmosphere”, which he said impeded his ability to perform his role as union president, in particular during the current difficult times for the public school system.
In a separate statement, the SEW union announced that Arendt would be succeeded by Joëlle Damé, a primary school teacher from Pétange. The new president said she felt ready to tackle the new challenges ahead, whether at the level of basic education, secondary and higher education.
The SEW trade union leadership also cordially thanked Arendt for his commitment over the past 12 years as SEW president.
