A Belgian court on Wednesday ordered the government to draw up a pandemic law within 30 days or face the annulment of some of its anti-Covid restrictions.
The Brussels court of first instance made the order after a complaint by the Belgian League of Human Rights.
The Belgian government appealed the decision and insisted that several other jurisdictions had greenlit the measures, a statement said.
The legal tussle matches similar battles in the Netherlands and Germany, where anger against anti-virus restrictions has also landed in courtrooms.
"The aim of our action is to put the parliamentary debate back at the centre," Audrey Lackner, lawyer for the League, told AFP.
"The court has confirmed the illegality of the measures and asked the Belgian state to do what is necessary to make them legal," she added.
In Belgium, the lockdowns and restrictions to fight the spread of the coronavirus have all been ordered by ministerial decree, bypassing parliament.
The government has also been criticised by the European Commission for border controls that limit free movement between Belgium and fellow EU member states.
This state of affairs has annoyed civil libertarians and ministers have begun efforts to draw up an appropriate law for future pandemics that would involve lawmakers more closely in the process.
This, however, was expected to take much longer than the 30 days ordered by the court, putting the government of Prime Minister Alexander De Croo in difficulty.
Contacted by AFP, De Croo's office said the court ruling was being analysed.
Lackner said that besides the new law, the court found the government could scrap the measures or draw up a new ministerial decree that is more legally sound.
Belgium is in the midst of a fight against the third wave of the pandemic, with schools shut, borders closed and appointments required to access non-essential shops.
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