Russian opposition leader Alexei Navalny in intensive care after airport tea 'poisoning'

Russian opposition leader Alexei Navalny is in a coma in a Siberian hospital after what his spokeswoman said was a deliberate poisoning.

Mr Navalny, the country’s most vocal critic of President Vladimir Putin, was flying back to Moscow from the Siberian city of Tomsk when he began crying out in pain and the plane was forced to make an emergency landing.

"We assume that Alexei was poisoned with something mixed into his tea," a spokeswoman Kira Yarmysh said. "It was the only thing that he drank in the morning. Doctors say the toxin was absorbed faster through the hot liquid. Alexei is now unconscious."

A representative of the Omsk hospital where the 44-year-old is being treated said he was on a ventilator in intensive care, and in a serious but stable condition.

“There is no certainty that the cause is poison but this is one potential version,” hospital deputy head Anatoly Kalinichenko told journalists.

Mr Yarmysh accused doctors of “evasion” which she alleged “only confirms this is a poisoning”.

“Two hours ago they were ready to share any information, and now they are clearly playing for time and are not saying what they know,” she wrote on Twitter, adding that there was a heavy police presence at the hospital.

Mr Navalny is a Yale-educated lawyer with a wide following in Russia and a popular YouTube channel where he presents investigations into corruption by officials.

The father of two was barred from standing against Mr Putin in Russia’s most recent presidential election and has been repeatedly jailed for organising anti-Kremlin protests.

Last year he was hospitalised with an acute allergic reaction while in a Russian jail, which he and his doctor said could have been caused by a “toxic agent” although the official explanation was dermatitis. In 2017 he suffered a serious chemical burn in one eye after an assailant threw green dye in his face outside of his Moscow office.

Ms Yarmysh told Russian media she believed the alleged poisoning was linked to regional elections next month, in which Mr Navalny is promoting opposition candidates.

Mr Navalny has supported ongoing anti-Kremlin demonstrations in the Russian far-east, and has drawn comparisons between the current unrest in Belarus and what might await Mr Putin when he next faces a presidential election in 2024.

Photos on social media show the opposition leader drinking what appears to be tea in Tomsk airport before boarding his flight. The airport cafe’s owners told the Interfax news agency they were checking CCTV from the morning.

A video taken by a passenger on the plane shows stewards with first aid kits walking to treat a moaning Mr Navalny. In a later video he is transferred on a stretcher to an ambulance on the tarmac.

Mr Navalny is not the first critic of Mr Putin to be targeted. Five years ago, opposition leader Boris Nemtsov was killed in a drive-by shooting near the walls of the Kremlin. A group of Chechen men were jailed for the attack but questions remain over who ordered the killing.

Alexander Litvinenko, a former FSB officer who accused authorities of masterminding a series of apartment block bombings in 1999 to consolidate Mr Putin’s power, died in London in 2006 after being poisoned by a radioactive substance.

In 2018, opposition activist Petr Verzilov was hospitalised after an apparent poisoning. He survived and accused the intelligence services of being behind the attack.