(FILES) This file photo taken on August 21, 2020 shows Alexander Murakhovsky (C), chief doctor at Omsk Emergency Hospital No 1 where Alexei Navalny was admitted after he fell ill in what his spokeswoman said was a suspected poisoning, speaks to the media in Omsk, Russia. - Tests carried out on Russian opposition leader Alexei Navalny provide clear proof that he was poisoned by a chemical nerve agent, the German government said Wednesday, September 2, 2020, demanding explanations from Moscow. (Photo by Dimitar DILKOFF / AFP)