GENEVA - Countries must urgently cooperate to halt the spread of violent extremism around the globe, the United Nations said Tuesday, ahead of a high-level conference focused on preventing dangerous radicalisation.

Jehangir Khan, head of the UN Counter-Terrorism Centre, warned that the problem of violent extremism was “mushrooming” and constituted a “clear and present danger” worldwide. He noted that tens of thousands of foreign fighters, coming from more than 100 different countries, have flooded into conflict zones like Syria and Iraq, while home-grown extremists have wreaked havoc in Europe with deadly attacks like the ones recently in Brussels.

“Everybody is potentially affected by violent extremism. Nobody is spared,” Khan said, insisting that “the need for international cooperation has never been more than now.” The UN will co-host a conference on preventing violent extremism, drawing some 30 govt ministers including foreign ministers of Belgium, Switzerland, Egypt and Malaysia.

UN chief Ban Ki-moon will open Friday’s high-level segment in Geneva, alongside the foreign minister of co-host Switzerland. Counter-terrorism experts, representatives of regional organisations and social media companies will also figure among the more than 600 participants.

The conference is meant to take stock of worldwide efforts to halt violent extremism, after Ban in January launched a global action plan and asked all countries to come up with national plans to address the problem.