A general strike has been called by the three unions representing workers on Brussels' public transport network Friday, to coincide with the first day of the European summit in the city.
The strike will start Friday around 4am and all public transport will be stopped.
Services will resume on Saturday. The unions are protesting against productivity measures and the redistribution of staff bonuses.
The 25 heads of state are due to meet in Brussels for a two day summit to discuss a new EU constitution.