Here are the main developments in the poisoning of Kremlin critic Alexei Navalny, who on Thursday accused President Vladimir Putin of being behind the attacked and vowed to return home.
– Admitted to hospital –
On August 20, the 44-year-old lawyer and anti-corruption campaigner is hospitalised in intensive care in the Siberian city of Omsk after losing consciousness while on a flight.
His entourage says he has been poisoned, while Russian doctors treating him say they have found “no trace” of poison in his blood or urine.
– Transferred to Berlin –
Two days later, in a medically induced coma, he is transferred to the Charite hospital in the German capital at his family’s request.
The Russian medical team treating him had initially refused the move.
On August 24, German doctors say tests indicate poisoning.
On August 27, the Russian judiciary announces it has launched a preliminary probe and says there is no proof of a poisoning.
– Novichok –
On September 2, Berlin says medical tests carried out by a German army laboratory have yielded “unequivocal evidence” that Navalny was a victim of poisoning by Novichok, a Soviet-era chemical weapon.
German Chancellor Angela Merkel seeks clarification from Moscow.
– International pressure –
NATO, followed by the European Union, demands an investigation.
On September 3, the Kremlin rejects claims that Moscow was behind the poisoning.
On September 4, a Russian toxicologist says Navalny’s health could have deteriorated because of dieting, stress or fatigue, insisting no poison had been found in the tests conducted in Siberia.
NATO Secretary General Jens Stoltenberg demands Moscow reveal its alleged Novichok programme to the global chemical weapons watchdog.
On September 6, Germany, which holds the rotating presidency of the European Union, says it will discuss possible sanctions against Russia.
– Out of coma –
On September 7, the Berlin hospital says Navalny emerges from a medically induced coma and is responsive.
– Labs confirm poisoning –
On September 14, laboratories in France and Sweden confirm Germany’s findings that Navalny was poisoned with a Novichok nerve agent.
French President Emmanuel Macron urges Putin by telephone to urgently shed light on the “attempted murder”.
Putin condemns “unsubstantiated” accusations.
– Out of hospital –
On September 15 Navalny posts a message on Instagram saying he is able to breathe unaided, appearing with his wife Yulia and two children, wearing a hospital gown and sitting up in bed, looking gaunt.
Two days later aides of Navalny say they have discovered traces of a Novichok nerve agent on a bottle taken from the hotel in Siberia where he stayed before falling ill.
On September 21 Navalny says Western laboratories have found traces of Novichok in and on his body and he demands Moscow return his clothes from the day he fell ill.
The next day Navalny is discharged and the Berlin hospital says a “complete recovery is possible”.
On September 23, the Kremlin says that Navalny is welcome to return to Moscow.
Navalny “will for now remain in Germany because his treatment is not over,” his spokeswoman says, adding a day later that Russia froze his assets while he was in a coma.
– Putin accused –
On October 1, Navalny accuses Putin of being behind his poisoning, and says he will not give the Russian president the pleasure of being in exile, in his first interview published since he left the hospital.
Putin’s spokesman Dmitry Peskov accuses Navalny of working for the CIA and calls his claims “groundless and unacceptable.”