The UN's human rights chief condemned the continued jailing of a leading figure in Russia's political opposition on Wednesday, demanding that he face "fair proceedings" for his opposition to the Russian invasion of Ukraine.
Volker Turk, the UN High Commissioner for Human Rights, was "concerned by continued detention of opposition politician and journalist Vladimir Kara-Murza since April 2022," his office said in a tweet.
The UN rights chief, it added, "calls for fair proceedings and his right of defense to be upheld."
Kara-Murza, long a thorn in the side of Russian President Vladimir Putin, was jailed last year for denouncing the Kremlin's war in Ukraine and has been charged with high treason, which could see him jailed for two decades.
Before the treason charge was added in October, the 41-year-old already had two criminal cases against him, which could potentially lengthen his sentence further.
When he was detained in April, he was put on the Russian foreign agent list — a label reminiscent of the "enemy of the people" branding that was used extensively throughout the Soviet Union to isolate dissidents.
And in August, he was accused of taking part in the activities of an "undesirable organization" for organizing a conference in support of Russian political prisoners.
The Western-educated activist and journalist was a close associate of both opposition leader Boris Nemtsov, who was shot dead near the Kremlin in 2015, and Mikhail Khodorkovsky, a former oligarch who is now a Putin critic.
Kara-Murza, who was awarded the Council of Europe's Vaclav Havel Human Rights Prize last year, claims he was poisoned twice because of his political activities, but he continued to live in Russia.
Kara-Murza, a Russian citizen by birth, has also been a British citizen after moving to Britain with his mother when he was 15.