BRUSSELS (AP) — An international conference of far-right politicians and supporters resumed in Brussels on Wednesday after the organizers launched a legal challenge against the authorities in the Belgian capital who feared the event could pose a threat to public order.

Hungarian Prime Minister Viktor Orban was due to speak at the National Conservative conference, a gathering of stridently nationalist and fundamentalist Christians, a day after Nigel Farage, the man credited with taking Britain out of the European Union, addressed the crowd.

French far-right figurehead Eric Zemmour had been scheduled to criticize the EU’s new migrant and asylum rules at the event Tuesday but was turned away by police. Emir Kir, mayor of the Saint-Joss neighborhood where it was held, had ordered police to prevent people from entering.

Kir acted after a group of anti-fascists threatened to disrupt the meeting. Indeed, the group had harassed conference organizers in recent days, forcing them to change venues twice. No protesters were in sight hours after police began to shut the event down but around 50 gathered after most participants had left on Tuesday.

But after an overnight legal challenge, a Brussels judge put a stay on the closure order.

Earlier, the Belgian and British leaders expressed concern about developments.

Belgian Prime Minister Alexander De Croo, a liberal and opponent of the far right, called the shutdown unacceptable in a post on the X platform.

“Municipal autonomy is a cornerstone of our democracy but can never overrule the Belgian constitution guaranteeing the freedom of speech and peaceful assembly since 1830. Banning political meetings is unconstitutional. Full stop,” he wrote.

A spokeswoman for Rishi Sunak said the British prime minister thought the move was “extremely disturbing.”

“The prime minister is a strong supporter and advocator for free speech, and he believes that should be fundamental to any democracy,” spokeswoman Camilla Marshall said. “Cancelling events or cancelling attendance and no-platforming speakers is damaging to free speech and democracy as a result.”

The conference comes ahead of Europe-wide elections. As campaigning for the June 6-9 polls heats up, mainstream parties fear that disenchanted voters might turn to some of the people attending NatCon 2024, as the event is dubbed.