The EU and Britain imposed sanctions Thursday on senior Russian intelligence officers for their alleged role in hacking the computer network in the German parliament in 2015.
The head of the GRU military intelligence agency, Igor Kostyukov, and intelligence officer Dmitri Badin have been banned from EU soil and are subject to an asset freeze.
A GRU unit, alleged to be responsible for cyber attacks, has also been added to the EU sanctions list.
Britain, which formally left the EU in January, said it was joining the bloc in enforcing asset freezes and travel bans against the two officers and intelligence unit.
A cyber attack in April and May 2015 completely paralyzed the IT infrastructure of the Bundestag and the entire parliament had to be taken offline for days while it was fixed.
In a statement, the European Council said that "a considerable amount of data had been stolen" and that "the email accounts of several members of parliament, including that of Chancellor Angela Merkel" had been hit.
Merkel has publicly blamed Russia for the hacking.
British Foreign Secretary Dominic Raab said: "The UK stands shoulder to shoulder with Germany and our European partners to hold Russia to account for cyber attacks designed to undermine Western democracies.
"This criminal behavior brings the Russian Government into further disrepute," he added.
Kostyukov was already on another EU sanctions list. In January 2019, he was banned from entering the UK and bank accounts allegedly link to him in the EU were frozen because of the nerve agent attack on British-based former double agent Sergei Skripal.
Badin had already been identified by German investigating authorities as the suspected mastermind behind the attack on the Bundestag.
An arrest warrant was issued against him by Germany's Federal Public Prosecutor General in May. The U.S. FBI is seeking Badin on suspicions of having influenced the presidential election of 2016.
According to the European Council, Badin is alleged to have worked for the GRU's 85th Main Center for Special Services (GTsSS) — a notorious cyber unit also known as "APT28" and "Fancy Bear."