None of the three airlines immediately responded to requests for comment.
The closure is also causing concern among trade unions, which fear passenger traffic may not return to pre-closure levels once the airport reopens.
“We have been insisting with the airport management for at least two years to have a dialogue on the subject,” said Alain Goelens, a representative of trade union SETCa, referring to the impact of the traffic suspension on employment.
He called for greater coordination between the airport and the Walloon regional government “to see how we are going to anticipate things, both for the staff and in relation to the airlines, to be sure that these companies will return.”
Cécile Neven, the Walloon minister responsible for airports, rejected accusations that the government had failed to plan.
“Contrary to what has been claimed, preparations for this project have been underway for many months,” her office said.