The European Union on Thursday denounced a Russian court ruling that branded "extremist" the political organisations of jailed Kremlin critic Alexei Navalny and barred them from working.

Axar.az reports citing foreign media that the statement said the move was intended "to eliminate Mr Navalny's political networks' influence ahead of the State Duma elections in September, and beyond."

"Yesterday's ruling by a Moscow Court to label Mr Alexei Navalny's organisations as 'extremist groups' marks the most serious effort to date by the Russian Government to suppress the independent political opposition and anti-corruption investigations," EU foreign policy chief Josep Borrell said in a statement on behalf of the 27 member states.

The EU has slapped sanctions on 10 senior Russian officials over last year's poisoning of Navalny with a Novichok nerve agent and his arrest and sentencing this year.

Moscow hit back by imposing entry bans on a number of Europeans, including high-ranking EU officials.