Alexei Navalny, a fierce critic of President Vladimir Putin, is in serious condition after drinking tea on Thursday morning that his allies believe was laced with poison.

Russian opposition leader Alexei Navalny smiles during an interview with AFP at the office of his Anti-corruption Foundation in Moscow on January 16, 2018.
Russian opposition leader Alexei Navalny smiles during an interview with AFP at the office of his Anti-corruption Foundation in Moscow on January 16, 2018. (AFP)

Doctors at the Siberian hospital where Russian opposition politician Alexei Navalny lies in a coma after suspected poisoning have allowed his family to transport him to a top German medical facility.

"We... took the decision that we do not oppose his transfer to another hospital, the one that his relatives indicate to us," the deputy chief doctor of the Omsk hospital, Anatoly Kalinichenko, told journalists on Friday.

Navalny, a 44-year-old politician and corruption investigator who is one of Russian President Vladimir Putin's fiercest critics, was admitted to an intensive care unit in the Siberian city of Omsk on Thursday. 

His supporters believe he was poisoned and that the Kremlin is behind it. 

The decision to grant Navalny's family permission to transfer him to Germany comes after allies of the opposition leader Alexei Navalny appealed to the European Court of Human Rights (ECHR) for help with their bid to get him transported. 

They accuse Russia of thwarting his medical evacuation, saying the decision placed his life in mortal danger because the Siberian hospital treating him was under-equipped.

Navalny is in a serious condition after drinking tea on Thursday morning that his allies believe was laced with poison. 

A doctor on Friday said his condition had improved a little overnight.

Ready to fly

German doctors who flew overnight to Omsk to transport him to Berlin said that he is in a fit state to be airlifted, the German activist organisation that sent the plane said on earlier on Friday.

Doctors in the Siberian city earlier said that Navalny's medical condition did not permit him to be moved. 

"We heard back from the German medical team that they are able and willing to fly Mr Navalny to Berlin, and that this is also the wish of his family," the Cinema for Peace Foundation said in a statement.

"The Russian authorities state that they consulted with the German doctors and that it is not safe for him to travel. This is incorrect," the statement continued.

Navalny's wife appeals Putin

Navalny's wife Yulia appealed to President Putin on Friday to allow him to be flown to Germany.

Earlier, Yulia and Navalny's spokeswoman Kira Yarmysh, spoke out against the Kremlin after the head doctor at the hospital in Siberia said moving him would put his life at risk because he was still in a coma and his condition unstable.

"The ban on transporting Navalny is an attempt on his life being carried out right now by doctors and the deceitful authorities that have authorised it," Yarmysh wrote on social media.

She said doctors had previously consented to his being moved, but had withheld their agreement at the last minute.

"This decision, of course, was not made by them, but by the Kremlin," said Yarmysh.

READ MORE: Who is Alexei Navalny — Russian dissenter and Putin's foe?

German treatment

The Kremlin said on Thursday that medical authorities would promptly consider any request to move him to a European clinic and were being open about his medical condition.

The row broke out as a German air ambulance landed in Omsk, the city where Navalny is being treated, with the intention of flying him to Germany for treatment if possible.

Alexander Murakhovsky, the hospital's head doctor, told reporters that many legal questions would need to be resolved before Navalny could be handed over to European doctors however.

He said top doctors had been flown in from Moscow to treat Navalny. The Moscow doctors were no worse than their European counterparts, he said.

Was Navalny definitely 'poisoned'? 

There were five possible diagnoses of Navalny's condition and test results would be available within two days, he said.

Murakhovsky declined to answer a question about whether Navalny had definitely been poisoned.

Navalny's team cited a police officer as saying a highly dangerous substance had been identified in his body that posed a risk to everyone around him who should therefore wear protective suits.

Reuters could not independently confirm that information.

Navalny's team said it believed authorities wanted to stall for time so that any trace of what poisoned him would disappear. 

READ MORE: Russia opposition leader Navalny hospitalised with 'poisoning'

A threat to Putin's grip on power

Like many other opposition politicians in Russia, Navalny has been frequently detained by law enforcement and harassed by pro-Kremlin groups.

In 2017, he was attacked by several men who threw antiseptic in his face, damaging an eye.

Last year, Navalny was rushed to a hospital from prison, where he was serving a sentence following an administrative arrest, with what his team said was suspected poisoning. Doctors said he had a severe allergic attack and discharged him back to prison the following day.

Navalny's Foundation for Fighting Corruption has been exposing graft among government officials, including some at the highest level. Last month, he had to shut the foundation after a financially devastating lawsuit from Yevgeny Prigozhin, a businessman with close ties to the Kremlin.

Belarus' authoritarian President Alexander Lukashenko accused Navalny last week of organizing unprecedented mass protests against his re-election that have rocked Russia's ex-Soviet neighbor since August 9. 

He did not, however, provide any evidence and that claim was one of many blaming foreign forces for the unrest.

'Poisoning' linked to elections? 

The most prominent member of Russia's opposition, Navalny campaigned to challenge Putin in the 2018 presidential election, but was barred from running.

He set up campaign offices across Russia and has been promoting opposition candidates in regional elections, challenging members of Russia's ruling party, United Russia.

In the interview with Echo Moskvy, Yarmysh said she believed the suspected poisoning was connected to this year's regional election campaign.

Commentators say Navalny has become increasingly dangerous for the Kremlin as Putin’s approval rating has plummeted to a record low of around 60 percent amid the coronavirus pandemic and growing public frustration with the declining economy.

Source: TRTWorld and agencies