The CGSP union criticized the Arizona coalition government for negatively impacting public service workers and users through cuts in personnel and operations.

A strike notice was also filed at RTBF to protest against budget cuts threatening public service integrity, including media functions.

Rail services were also affected, with only three out of five intercity trains running and about 50% of local trains operational.

Key issues raised by the union include the dismantling of pension systems, reductions in social security, and the erosion of civil service status.

On May 20, 2025, a general strike organized by the socialist union commenced in response to the Arizona government's measures against public services.

In Liège, courts announced cancellations of many hearings due to staff shortages, while a work stoppage and rally were scheduled in Brussels from 9 AM to 10 AM at Place Poelaert.

As part of the strike activities, a gathering was held in front of the Pension Tower near Brussels Midi station in the morning.

Despite the disruptions, national and Charleroi airports reported no significant disruptions, and flights were expected to proceed normally.

In Brussels, partial operations were expected for metro lines 1 and 5, as well as various bus and tram lines, while users were advised to check transport websites for updates.

This strike marks the beginning of a socially charged week, leading up to a planned demonstration for the non-profit sector on May 22, 2025, in Brussels.

Waste collection services were disrupted, with many recycling centers closed and some collection rounds canceled, leading to potential delays in waste management.

Bpost anticipated delays in mail and package deliveries but promised to keep customers informed through tracking systems.

On the TEC network in Liège-Verviers, only 80 out of 204 bus lines were operating normally as of early morning.