Volker Türk said the 19-year sentence was based on vague and overly broad charges of “extremism” and followed a closed trial on the premises of the prison where Mr. Navalny is already serving two other sentences amounting to 11 and a half years.

He recalled that under international human rights law, States have an obligation to respect, protect and fulfil the full range of fair trial and due process rights to all individuals deprived of their liberty.

“I call on the Russian authorities to take measures to respect these obligations by immediately ceasing violations of Navalny’s human rights and release him,” the rights chief said.

Repressive crackdown

Mr. Türk said this latest sentence against Mr. Navalny comes amid an increasingly repressive crackdown on freedom of expression and political opposition in Russia.

Since February 2022, some 20,000 people have been arrested, many of them briefly, for various actions against Russia’s war against Ukraine, including protesting and posting on social media.

Several were jailed for allegedly spreading false information about the actions of the military and hundreds more have been given administrative fines for “discrediting” the Russian Army, he added.

There has also been a sharp increase in the use of the espionage and treason provisions of the Criminal Code to try and convict people that were merely exercising their human rights.

Mr. Türk called for a transparent and impartial review of such cases, in accordance with international human rights norms.

“Deprivation of liberty for the exercise of human rights, including the freedom of opinion, expression, peaceful assembly and association, constitutes arbitrary detention under international human rights law,” he said, adding that “all those arbitrarily detained should be released immediately.”

The UN Secretary-General supports the High Commissioner's statement, his Deputy Spokesperson said during the daily press briefing at UN Headquarters in New York.