Alexei Navalny: who is the Russian politician and anti-corruption activist, what is Novichok and who is responsible for poisoning?

Alexei Navalny is one of Vladimir Putin's most vocal opponents (Getty Images)

Alexei Navalny was poisoned with nerve agent Novichok, the German government has said.

Prominent Vladimir Putin opponent Alexei Navalny remains in a coma and on a ventilator in a hospital intensive care unit, after claims that he was poisoned Russia's Siberia region last month. his team have claimed that he was poisoned on the orders of Russia president Vladimir Putin.

The opposition leader was transported from a hospital in Omsk to Germany where doctors said tests indicated he was poisoned.

Prime Minister Boris Johnson has called for a transparent investigation into the incident.

The German government said: "It is a disturbing development that Alexei Navalny was the victim of a chemical nerve agent in Russia.”

What happened to Alexei Navalny?

The 44-year-old felt unwell on a flight back to Moscow from Tomsk, a city in Siberia.

Mr Navalny’s spokeswoman Kira Yarmysh suggested he may have consumed something in a cup of tea he drank at an airport cafe before boarding the plane.

During the flight Mr Navalny started sweating and asked her to talk to him so he could “focus on a sound of a voice”. He then went to the toilet and lost consciousness.

Anatoliy Kalinichenko, deputy chief doctor of the hospital in Omsk, Siberia, where Mr Navalny is being treated, said he was in grave but stable condition.

Doctors say no poison was found in his body, but his supporters believe that a poisonous substance could have been put in to his drink at an airport cafe in Tomsk as he prepared to fly to Moscow.

Medical professionals have currently deemed Mr Navalny too ill to be transferred to Germany for further medical attention.

Who’s responsible?

Allies of the politician have claimed the Kremlin is behind the illness of its most prominent critic, with some demanding an investigation into whether Mr Putin was involved.

But Kremlin spokesman Dmitry Peskov told reporters this week: “These accusations absolutely cannot be true and are rather an empty noise.

“We do not intend to take it seriously.”

Who is Alexei Navalny?

Mr Navalny is one of the most prominent opposition figures in Russia and campaigned to challenge Mr Putin in the 2018 presidential election, but was barred from running.

He has gained prominence in Russia politics for his opposition to corruption, Vladimir Putin and the ruling government.

In 2011 he was imprisoned for 15 days after protesting against vote rigging allegedly carried out by Putin’s United Russia party.

He ran in the 2013 Moscow mayoral election, finishing second to a Putin appointee. Navalny has since claimed that he received more votes and the election was subject to fraud.

Navalny has been arrested on several occasions, receiving suspended sentences for embezzlement on two occasions, both of which supporters of Navalny claim to be fabricated.

Mr Navalny had dye thrown in his eye in 2017 suffering a serious chemical burn as a result, but it’s unclear who carried out the attack.

Mr Navalny’s Foundation for Fighting Corruption has focused on exposing sleaze among government officials, but last month he had to shut the organisation after a financially devastating lawsuit from Yevgeny Prigozhin, a businessman with close ties to the Kremlin.

Mr Navalny has also been accused by Belarus’s authoritarian leader Alexander Lukashenko of organising the mass protests against his rule in recent days following an election which has been widely criticised as rigged.

Wall Street Journal described Navalny as “the man Vladimir Putin fears most”.

What is Novichok?

Translating as ‘new boy’ or ‘beginner’ Novichok is a series of nerve agents developed by Russia and the Soviet Union between 1971 and 1993.

Developers say they are the most deadly nerve agents ever developed.

The agent was designed to be undetectable, capble of breaching NATO protective gear, safer to handle and capable of circumventing the Chemical Weapons Convention list.

A former Russian double agent who passed secrets to British intelligence was poisoned with the nerve agent along with his daughter in 2018 when in Salisbury. Both recovered, though one local woman who came into contact with the substance died.

Previous poisoning victims with ties to Vladimir Putin

Several of Vladimir Putin’s most fierce opponents have been the victims of poisoning.

A former Russian double agent who passed secrets to British intelligence was poisoned along with his daughter in 2018 when in Salisbury. They had been poisoned with nerve agent Novichok while in the English town, though both recovered.

Ex-KGB agent and vocal Putin critic Alexander Litvinenko died after he was poisoned after drinking green tea laced with polonium-210 in 2006. A British inquiry concluded in 2016 that Vladimir Ptin likely approved the killing.

Ukrainian opposition leader Viktor Yushchenko claims he was poisoned by the Russian state in 2004 while running in the Ukraine presidential election.

He claims he was poisoned with dioxin while dining with security officials. The poisoning left his face disfigured an in need of several operations.