​US sends message to Russia over poisoning ​

The US ambassador to Moscow has urged Russia to immediately launch an investigation into the alleged poisoning of Kremlin critic Alexei Navalny who is undergoing treatment in Germany.

John Sullivan said the Russian authorities should open an “immediate, comprehensive, and transparent investigation” that holds the parties behind this act responsible, his spokeswoman wrote on Twitter.

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It comes as the Kremlin accused German medics of being too hasty after they said tests on Russian opposition leader Alexei Navalny indicated he was poisoned.

The 44-year-old Navalny, who is one of the fiercest critics of President Vladimir Putin and has exposed massive official corruption, is being treated in a Berlin hospital after falling ill on a flight in Siberia last Thursday.

He was treated for two days in a hospital in Siberia before being transferred to the Charite clinic.

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Charite doctors said Monday that clinical tests on Navalny “indicate poisoning with a substance from the group of cholinesterase inhibitors”.

These are substances used in nerve agents as well as medicines and insecticides that suppress an enzyme needed for the central nervous system to function normally.

Navalny’s supporters claim he was poisoned by something in his cup of tea at a Siberian airport before a flight to Moscow, pointing the finger of blame at Putin.

Kremlin spokesman Dmitry Peskov told journalists it was not clear whether Navalny had been poisoned because the substance responsible has not been identified. Russia will not open a criminal investigation until this happens, he said.

Peskov claimed Russian medics had diagnosed Navalny’s condition in a similar way to German doctors but said the Germans had rushed to conclude that Navalny was poisoned.

“The medical analysis of our doctors and the German ones absolutely matches. But the conclusions differ. We don’t understand why our German colleagues are in such a hurry. The substance hasn’t yet been established,” he told journalists.

Russia has not opened a criminal investigation into the poisoning and Peskov said there was “no pretext” for this until the substance causing Navalny’s condition is identified.

The EU has urged Russia to hold a “independent and transparent investigation” while German Chancellor Angela Merkel called for those responsible to be held accountable.

The French foreign ministry said it was profoundly concerned over the “criminal act” and urged a “swift and transparent investigation” to bring those responsible to justice.

RELATED: Vladimir Putin opponent Alexei Navalny critical after poisoning

Navalny is the latest in a long line of Kremlin opponents to fall seriously ill or die from poisoning, either suspected or proven.

The nerve agent Novichok was used against former Russian double agent Sergei Skripal and his daughter Yulia in Britain in 2018. Two Russian military agents identified by Britain as suspects have disappeared from view.

In 2006, former Russian security service agent Alexander Litvinenko died in London after drinking tea laced with radioactive polonium-210. Russia refused to extradite the chief suspect, Andrei Lugovoi.

The Kremlin reaction angered Navalny’s allies.

“It was obvious that the crime would not be properly investigated and the criminal found, though we know very well who he is,” tweeted his spokeswoman Kira Yarmysh.

“But the particular way Peskov talks about this makes me rage.”

Peskov cast doubt on the German government’s statement that Navalny “fairly likely was poisoned,” saying there were other possible explanations.

“We can only partially agree … There is a likelihood of something else too.” He acknowledged that poisoning “can be seen as one of the versions, but there are a lot of other medical versions”.

Peskov said Russian medics at the hospital in the Siberian city of Omsk had also detected a low level of the cholinesterase enzyme and treated Navalny with the antidote atropine, as the German medics are doing.

The chief toxicologist at the Omsk hospital, Alexander Sabayev said Monday that Navalny tested negative for cholinesterase inhibitors, however.

The Russian doctors earlier suggested that Navalny had a “metabolic disorder” and low blood sugar.

Navalny previously said he was poisoned in July 2019 after suffering rashes and a swollen face in prison, although no investigation was opened.

He was attacked in 2017 by pro-Kremlin activists who threw green dye at his face, causing chemical burns to his eye.