EU foreign ministers agreed on Monday to sanction four senior Russian officials in response to the treatment of Kremlin-critic Alexei Navalny.
Those to be targeted with asset freezes and travel bans all have close ties to Russian President Vladimir Putin.
Navalny was arrested and jailed after returning to Moscow last month from Germany, where he had been recovering from a near-fatal poisoning in Siberia.
Several European authorities have said that Navalny was targeted with a novichok nerve agent developed in Russia.
The Kremlin has denied this.
The sanctions are the first under the EU's new system to punish human rights violators and ban them from entry into the bloc.
EU foreign policy chief Josep Borrell:
"In response to events around the situation of Mr Navalny, we have reached a political agreement to impose restrictive measures against those responsible for his arrest and sentencing and persecution. And for doing that, for the first time ever, we will make use of the European Unions global human rights regime to this end."
The EU has already sanctioned six Russians and a state scientific research center in response to the treatment of Navalny.
But pressure has been growing for it to do more after Moscow expelled German, Polish and Swedish diplomats earlier this month.
An EU diplomat gave details of those who are included on the draft list to be sanctioned.
Among them is Alexander Bastrykin, head of Russia's powerful Investigative Committee, and Igor Krasnov, Russia's prosecutor-general.
The list falls short of the demands made by Navalny's allies, who have drawn up a list of 35 people they want targeted, including several of Russia's business leaders.
Still - the sanctions have drawn the ire of Moscow, with Russia's foreign ministry calling them unlawful and a cause for disappointment.