From 21 to 25 November 2015, the government of Belgium imposed a security lockdown on Brussels, including the closure of shops, schools, public transportation, due to information about potential terrorist attacks in the wake of the series of coordinated terrorist attacks in Paris by Islamic State of Iraq and the Levant on 13 November.

"[10][11][12] The lockdown caused disruption to major institutions and organizations headquartered in the city, such as NATO, which removed all non-essential personnel on 23 November, and the European Union, which opened on Monday with reinforced security measures.

"[12] After 5 days, the lockdown was lifted on 25 November, schools reopened and the metro resumed service[14] but some stores remained closed.

[16] The lockdown is estimated to have cost €51.7 million per day, counting both the outlay on security and lost business income.

[17] Belgium is also facing a demand from the police for a budgetary increment of €100 million to cover ongoing increases in costs due to the terrorism threat.

He said during his speech, "My special thanks go to all those who have fought for it and continue to work to ensure our safety, to identify the perpetrators of these attacks and to prevent new ones.