The two largest unions voted last week to go on strike on Friday this week if the airport operator, Brussels International Airport Company, did not come up with a better offer.

Union spokesman Jan Francois told VRT television he could not rule out wildcat strike action before Friday, however, which could force a shutdown of the airport, if the 750 staff, including essential firefighters, security, administration and logistics teams join the picket line.

Paul De Backer, spokesman for BIAC, said talks were continuing with the two main unions to get a deal before Friday. A strike would cause major problems during the busiest travel period of July and August, when most Belgians take their summer vacations.