The technical agreement, signed at NATO headquarters today, establishes a framework for emergency response teams from NATO and the EU to exchange information and share best practices, Stoltenberg told reporters.
Since Russia's 2014 annexation of Crimea, NATO and the EU, which have 22 member countries in common, have accelerated cooperation in a number of defense-related fields.
In a statement, the European Union said the new agreement will facilitate information-sharing to improve cyber incident prevention, detection and response at both the EU and NATO.