Brussels airport remained closed for passenger flights on April 1, as airport authorities and police could not agree on how to screen passengers arriving for flights following the March 22 suicide bombings.
The airport, whose departure hall was destroyed by the blasts, has built a temporary check-in zone and conducted extensive tests before announcing it was partially ready to resume flights.
The federal police want passengers to be checked outside the new departure zone.
But the airport authorities disagree, saying that would simply shift the security threat from inside to outside the area.
"We need an agreement with the police unions," an airport spokeswoman said on April 1.
Belgium media reported that airport police -- in an open letter -- complained about what it described as poor security at the airport, including a lack of checks on people and luggage entering the airport building.
They reportedly claimed that at least 50 Islamic State sympathizers worked in the airport and had security badges.
Meanwhile, Brussels banned a rally by a French far-right group that was planned to take place on April 2 in the Molenbeek neighborhood.
Molenbeek is home to several suspects linked to deadly attacks in Brussels and Paris.
The rally was announced under the motto: "Let's expel the Islamists."