More unions could join future strikes if no deal is reached

The strike has forced the cancellation of trains, including international services such as Eurostar.

The protest was called by Belgium's Socialist FGTB/ABVV union in protest at government plans to stop workers retiring early with full benefits.

The 24-hour stoppage is the first general strike in Belgium since 1993.

The Belgian government has urged people to work from home, if possible.

Postal workers at sorting offices walked out on Thursday evening and airport authorities warned of possible disruption to flights.

Local media reported that one tram was running in Brussels because it left before strikers picketed the depot.

There were also pickets and blockades at factories and ports. Antwerp, one of Europe's largest ports, was shut for business as dockers refused to work.

Talks due

Joining a picket line in Charleroi, Jean-Claude Vandermeeren, general secretary of the Walloon branch of the General Federation of Belgian Labour, urged the government to heed the workers' message.

"If the political world, the Socialist Party in particular, does not understand that people are protesting in the streets, that people have stopped working, and you can see it here with nobody showing up for work - this is just a symbolic picket," he said.

"If the Socialist Party can see this for itself and not find it serious and think that there is no problem, then I no longer understand anything in politics."