EU member states on Monday approved sanctions to be slapped on four senior Russian justice and law enforcement officials involved in the detention of Kremlin critic Alexei Navalny.

Diplomatic sources told AFP the names would be published in the bloc's official journal on Tuesday, after envoys from member states approved the list of targets drawn up by Brussels.

According to two sources, speaking on condition of anonymity, the targeted Russians are: Alexander Kalashnikov, federal prisons administrator; Alexander Bastrykin, head of the Investigative Committee of Russia; Igor Krasnov, prosecutor general; and Viktor Zolotov, director of the National Guard.

The four are the first individuals to be targeted under the EU's new human rights sanctions regime, which came into effect in December. They will be banned from travelling to the EU and any assets held there will be frozen.

Navalny was jailed last month after returning to Moscow from Germany, where he had spent months recovering from a poisoning with a banned nerve agent he blames on Putin. The Kremlin denies it was behind the attack. 

The imprisoning of Putin's best-known opponent sparked nationwide protests that saw thousands of demonstrators detained and triggered calls in the West for Navalny's release -- calls now backed by EU sanctions.

Russia's deputy foreign minister Alexander Grushko said Russia would respond, without giving details.

"It's not a surprise for us. The European Union is continuing along an absolutely unlawful path that is an absolute dead-end," he said, according to Interfax.