The head of the intoxication department at the Omsk hospital, where Alexei Navalny was hospitalised on 20 August, said on Thursday as quoted by Rossiya 24 broadcaster that doctors checked the opposition figure for poisoning but didn't find anything.
"Phosphoorganic bindings were the first toxic substance we looked for," Alexander Sabaev said, adding that these elements were "not confirmed."
Specialists tested Navalny for a wide range of substances, Sabaev said.
"But our main task was to exclude strong poisons," the doctor said.
Sabaev remarked that other people would have suffered if Navalny had been poisoned with a Novichok-type nerve agent.
At the same time, doctors from the Moscow Institute of Emergency First Aid named after Nikolay Sklifosovsky stated that no traces of a substance from the group of cholinesterase inhibitors were found in Navalny's body.
The statement comes a day after Berlin claimed that a German military laboratory possessed undeniable proof of 44-year-old Navalny's poisoning with a nerve agent from the Novichok group.
Responding to the claims, Russian Foreign Ministry spokeswoman Maria Zakharova noted that the German government's position lacks evidence, and added that it was perplexing why Berlin first addressed the EU, NATO and third parties, such as the Organisation for the Prohibition of Chemical Weapons (OPCW), in relation to the case, instead of contacting Russia directly.
On 20 August, Russian opposition figure Alexei Navalny fell gravely ill during a domestic Russian flight. Following an emergency landing in the Siberian city of Omsk, he was taken to a local hospital and, according to regional doctors, he arrived just 17 minutes after landing.
For the next 44 hours, doctors waged an uninterrupted struggle for his life, as he went into a coma and was put on an artificial lung ventilator.
Upon conducting multiple tests, Russian medics established that no traces of poison had been found in his system, saying that Navalny's condition was caused by an abrupt drop of glucose in his blood due to a metabolic imbalance.
On 22 August, Navalny was flown to Berlin for further treatment. German doctors claimed that they had found traces of a substance from the group of cholinesterase inhibitors in his body, which the Russian doctors denied, referring to his test results.