On 19 July 2017, the European Council agreed to develop a framework that allows a joint EU diplomatic response to cyber attacks. The framework provides for the possibility to implement restrictive measures within the Common Foreign and Security Policy in case of cyber attacks. The EU is concerned by the increased ability and willingness of state and non-state actors to pursue their objectives through malicious cyber activities and deems it necessary to be able to respond to such activities through the introduction of this framework. According to the EU press release, a joint EU response to cyber activities would be proportionate to the scope, scale, duration, intensity, complexity, sophistication and impact of the cyber activity.
The European Council press release can be found here.