Brussels, May 5, 2026

The European Union has tested its mutual assistance clause to prepare for a potential large-scale hybrid attack.

Preparing for Hybrid Threats

The exercise, involving ambassadors and experts from EU member states as well as European institutions, aimed to evaluate crisis response and coordination in the event of a hybrid attack. Such attacks include cyberattacks on power grids, illegal drone flights, and acts of sabotage. The results will be used to develop a plan to strengthen the EU mutual assistance clause.

The EU is also exploring scenarios in which it could intervene in addition to NATO. The Union's mutual assistance clause is more strongly worded than NATO's Article 5 collective defense provision. So far, it has only been activated once—following the 2015 Paris terror attacks. At that time, Germany increased its involvement in the fight against the Islamic State in Iraq and Syria.