Tests indicate that leading Russian opposition figure Alexei Navalny was poisoned, the Berlin hospital where he is being treated said on Monday.

German Chancellor Angela Merkel immediately called on Moscow to fully investigate the suspected poisoning and to identify and hold accountable those responsible.

She said in a joint statement issued with Foreign Minister Heiko Maas.

“In view of the prominent role of Mr Navalny in the political opposition in Russia, the authorities there are now urgently called upon to investigate this act down to the last detail – and in full transparency,” she said.

Those responsible “must be identified and held accountable,” the statement said.

It did not mention Russian President Vladimir Putin by name.

Merkel and Maas also expressed the hope that Navalny would make a full recovery and extended their best wishes to his family.

The Charite hospital said the precise toxin remains unknown, but they assume the substance came from a group of cholinesterase inhibitors, which prevent the breakdown of certain neurotransmitters.

While 44-year-old Navalny’s state of health was serious, there was no acute danger to his life, a spokesperson said.

She said the prognosis remained uncertain, and long-term consequences, in particular for the nervous system, could not be ruled out at this stage.

Navalny became ill on a flight from the Siberian city of Tomsk en route to Moscow on Thursday, and the airliner made an emergency landing in the Siberian city Omsk.

He was initially treated in Omsk before doctors there agreed, following a lengthy wrangle, to allow him to travel to Germany.

He was flown to Germany on Saturday for emergency treatment at the Charite, Berlin’s leading hospital.

The hospital’s findings support the claims of Navalny’s team, which has pointed to poisoning as the likely cause from the outset.

They have suggested that tea he drank at an airport cafe in Tomsk may have been spiked.

The Russian hospital in Omsk had said there appeared to be no evidence of a malicious poisoning and suggested that Navalny had gone into a coma due to low blood sugar levels.

Navalny’s spokesperson, Kira Yarmysh, denounced the Omsk hospital’s conclusion.

She had accused Russian authorities of attempting to cover up a crime – that Navalny had been poisoned.

Yarmysh said the ambulance personnel that had brought Navalny to the Omsk hospital had said he appeared to have been poisoned.

“The very first doctor who saw Alexei made that conclusion. All the following days, the head doctor of the Omsk hospital just fooled everyone,” Yarmysh said in a statement on Twitter.

Navalny has been arguably the fiercest critic of Putin over the past decade, organising several series of protests against the long-time Russian leader, whom he accuses of perpetuating widespread corruption.

Navalny had been in Siberia to support opposition candidates preparing for local elections.

The Omsk hospital said on Monday that it had not been under any pressure from state authorities.

“We saved his life. There was no outside influence on the care for the patient and there couldn’t have been,” the Head Doctor at the Omsk hospital, Alexander Murakhovsky, said.

Murakhovsky said that any major decision about the Russian hospital’s care for Navalny had been decided by a council of up to 10 doctors representing various medical institutions. (dpa/NAN)

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