EU Council President Donald Tusk said Thursday that the leaders want EU "ministers to work on a sanctions regime that will be specific to cyberattacks."
Tusk said the system "should help to protect our citizens, companies and institutions from all kinds of cybersecurity threats."
Dutch officials alleged two weeks ago that four agents from Russia's GRU military intelligence agency tried and failed to hack into the Wi-Fi system at the Organization for the Prohibition of Chemical Weapons.
The leaders' demand comes amid concerns over possible election interference during the European Parliament vote in May.
Copyright 2018 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.