Russian dissident Alexei Navalny, being treated by doctors in Berlin, may have been poisoned by a nerve agent of the same or similar type to Novichok, which was used in the attempted assassination of Sergei Skripal and his daughter in the UK in 2018.

Navalny, who remains in a coma, is being treated with atropine, the same antidote used after the Salisbury attack. The news of his treatment came in a statement from the doctors at the Charité Hospital in Berlin.

The hospital said that the 44 year-old dissident had fallen ill due to contamination by a cholinesterase inhibitor, which blocks the enzymes essential for the proper functioning of the central nervous system.

The hospital said there is “currently no acute danger to his life.”

In an online statement, the hospital said: “Alexei Navalny’s prognosis remains unclear; the possibility of long-term effects, particularly those affecting the nervous system, cannot be excluded.”

Kira Yarmish, an aide to Navalny who was travelling with him when he became ill on a flight to Moscow, said: ”Now the poisoning has been confirmed. It is not a hypothesis any more, it is a medical fact.”

Poisoning has been used on several occasions over the past few years to get rid of dissidents and journalists who tread on the toes of Vladimir Putin, the Russian president.

PHOTO: Alexei Navalny with fans on an airport shuttle bus before his flight to Moscow, diverted to Omsk Instagram