By Tom McArthur, LONDON England
Russian opposition leader Alexei Navalny was killed using a poison developed from a dart frog toxin, the UK and European allies have said.
Two years on from the death of Navalny at a Siberian penal colony, Britain and its allies have blamed the Kremlin following analysis of material samples found on his body.
Speaking from the Munich Security Conference, Foreign Secretary Yvette Cooper said "only the Russian government had the means, motive and opportunity" to use the poison while Navalny was imprisoned in Russia.
According to Tass news agency Moscow has dismissed the finding as "an information campaign", but Cooper said there is no explanation for the toxin, called epibatidine, being found.
While Cooper announced the findings, a joint statement was issued by the UK, Sweden, France, Germany and the Netherlands.
Cooper met with Navalny's widow Yulia Navalnaya at the conference this weekend.
"Russia saw Navalny as a threat," Cooper said at the event.
"By using this form of poison the Russian state demonstrated the despicable tools it has at its disposal and the overwhelming fear it has of political opposition," she added.
In the statement the allies said: "Only the Russian state had the means, motive and opportunity to deploy this lethal toxin to target Navalny during his imprisonment in a Russian penal colony in Siberia, and we hold it responsible for his death.
"Epibatidine can be found naturally in dart frogs in the wild in South America. Dart frogs in captivity do not produce this toxin and it is not found naturally in Russia.
"There is no innocent explanation for its presence in Navalny's body."
The Foreign Office said the UK has informed the Organisation on the Prohibition of Chemical Weapons of Russia's alleged breach of the Chemical Weapons Convention.
Praising Navalny's "huge courage", UK Prime Minister Sir Keir Starmer said "his determination to expose the truth has left an enduring legacy".
"I am doing whatever it takes to defend our people, our values and our way of life from the threat of Russia and Putin's murderous intent," he added.
French Foreign Minister Jean-Noël Barrot also said his country "pays tribute" to Navalny, who he suggested was "killed for his fight in favour of a free and democratic Russia".
Navalny – an anti-corruption campaigner and Russia's most vociferous opposition leader - died suddenly in jail on 16 February 2024 at the age of 47.
In 2020 he was poisoned with a Novichok nerve agent. He underwent treatment in Germany, and was arrested at the airport upon his return to Russia.
Epibatidine, the toxin the UK and its European allies have said was used to kill Alexei Navalny, was first derived from a group of poison dart frogs native to northern South America.
Though epibatidine has previously been investigated as a pain killer and for relief from painful inflammatory conditions of the lungs, it has been deemed too toxic to use clinically.
Russian toxicology expert Jill Johnson told our reporter it was "200 times more potent than morphine".
By acting on receptors in the central nervous system, it can cause "muscle twitching and paralysis, seizures, slow heart rate, respiratory failure and finally death," Johnson said.
The extremely rare neurotoxin is only found in one wild frog species in tiny quantities, and only when the frog eats a specific diet, she said.
Researchers believe the frogs acquire it through their diet because animals from different habitats have displayed different levels of the toxin, and those raised in captivity have none.
Johnson described it as an "incredibly rare way to poison a person".
