Belgium reintroduced border controls with France on Tuesday to prevent a potential influx of UK-bound migrants if part of the "Jungle" camp in the French ferry port of Calais is demolished, reports The Telegraph.
The move, which is a blow to the 26-nation European passport-free Schengen zone, came as a legal challenge forced the French authorities to postpone a plan to demolish the southern section of the camp, where NGOs say 3,400 migrants are living in makeshift huts and tents while they try to smuggle themselves into Britain.
Eight NGOs have launched legal proceedings to delay the demolition until hundreds of unaccompanied minors can be given shelter. A court was to have issued a ruling on Tuesday. However, Judge Valérie Quemener visited the camp and said a decision would be made "within 48 hours".
The partial clearance of the jungle is a prelude to the removal of the entire camp. According to NGOs and police sources, it is home to up to 6,000 migrants, although the French government maintains that there are only half that number.
Border controls have been reinforced in Calais and along the northern French coast since last summer and migrants have been trying to cross the Channel instead from Belgian ports including Zeebrugge.
The Belgian interior minister, Jan Jambon, said: "We have informed the European Commission that we will temporarily depart from Schengen rules."
France and Belgium are part of the Schengen area which allows free movement without passport checks. Countries are allowed to suspend the arrangement in exceptional circumstances and Belgium wants to prevent the growing migrant crisis in Calais from spilling over the border.