The German official said the blood test results of Russian opposition leader Navalny showed that he was poisoned by the Novichok compound.

"Toxicity test in a blood sample of Alexei Navalny conducted in a German army laboratory gives clear evidence that he has been poisoned by Novichok. The government has informed the European Union partners.

The German official said it was "shocking news", asserting that Berlin would "condemn the attack with the strongest words".

Kremlin spokesman Dmitry Peskov said Germany had not directly informed Russia of the information that Navalny was suspected of being poisoned with Novichok, emphasizing that Moscow had not been informed of the new discovery.

Navalny, 44, leader of the opposition party of the Russian People's Union, felt unwell and unconscious while on a flight from Siberia to Moscow on August 20, forcing his plane to make an emergency landing.

Navalny was admitted to a hospital in Siberia, where doctors claimed there was not any evidence that Navalny was poisoned.

Siberian police announced last week that it had begun a "pre-investigation" process on the cause of Navalny's hospitalization in the city of Omsk.