"A vast police operation is currently underway in Brussels. Demonstrations are expected today, with the minimum of 10,000 participants that the organizers expect to see. The demonstration is scheduled to start marching at 06:00 p.m. local time [16:00 GMT]," the police official said.
The march will start at the Brussels-North Railway station, and then move to the city canal before returning back to the station. A number of speeches are expected to be made prior to the protests, which will be followed by concerts, whereas the whole event will finish by approximately 20:30 GMT, according to the police representative.
The "Trump not Welcome" initiative is held by students in Brussels and Ghent, and is supported by many civil organizations, including Doctors of the World, Greenpeace, Friends of the Earth Europe, Oxfam International.
According to the organizers' website, Trump "caused outrage all over the world, dividing and excluding people, denying climate change, intimidating the media, phasing out solidarity."