The top United Nations human rights official called on Russia on Tuesday (September 8) to conduct, or cooperate with, a full independent investigation into Germany's findings that opposition leader Alexei Navalny was poisoned with a Novichok nerve agent.
Moscow says it has seen no evidence he was poisoned.
German Chancellor Angela Merkel has said her government has concluded that Navalny, 44, was poisoned with Novichok, the same substance that Britain said was used against Russian double agent Sergei Skripal and his daughter, both of whom survived, in an attack in England in 2018.
"It is not good enough to simply deny he was poisoned, and deny the need for a thorough, independent, impartial and transparent investigation into this assassination attempt," Michelle Bachelet, U.N. High Commissioner for Human Rights, said in a statement.
Her spokesman, Rupert Colville, cited the Skripal case and the poisoning of Russian defector Alexander Litvinenko, who was killed in London in 2006.
Proper legal processes have not been carried out in previous incidents, resulting in "close to total impunity" in Russia, he said.