Putin's Kremlin had possession of frog poison used to kill Alexei Navalny, foreign secretary claims

Vladimir Putin’s Kremlin "has had possession" of the deadly frog toxin that was found in the body of Russian opposition leader Alexei Navalny, the UK’s foreign secretary has said.

Yvette Cooper also confirmed that the poison - found in the skin of Ecuadorian dart frogs - can also be manufactured in the laboratory and hinted that this could have been the case with the substance alleged to have killed the dissident, who died in a Russian prison two years ago.

She was speaking to Trevor Phillips on Sunday, a day after the UK and a group of allies announced that their scientists had discovered that Mr Navalny, 47, had been poisoned with the frog toxin - called epibatidine.

Classed as a chemical weapon, it is 200 times stronger than morphine and causes paralysis, respiratory failure and death.

Indigenous tribes in South America are said to use the toxin in blow darts or blowguns when they hunt. But it can also be produced synthetically.

Asked whether she could offer any details on whether the poison was manmade or had been taken from frogs, Ms Cooper said: "I can't tell you the details of that. But as you say, this is a particular chemical. It can be produced synthetically.

"It can also be found in this particular frog in Ecuador. And we do know that the Russian regime has had possession of this particular chemical. It is obviously not one that is found naturally in Russia."

She was also asked about the Kremlin’s response to the claims that it was behind the alleged murder of Mr Navalny, with the Russian embassy rejecting the allegations as nonsense. Russia has previously claimed the death was not suspicious.

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Ms Cooper said that Britain, Sweden, the Netherlands, France and Germany had spent the past two years investigating what happened to Mr Navalny at the penal colony in Siberia.

"We have worked with our European partners on pursuing the evidence and pursuing the truth," she said.

"And that is why we have together found the evidence of this lethal toxin that was found in Alexei Navalny's body at the time he died, and only the Russian regime had the motive, the means and the opportunity to administer this lethal poison while he was in prison in Russia.

"They wanted to silence him because he was a critic of their regime, and that's why we have exposed this barbaric Kremlin plot to do so and made sure that we have done so with evidence."

(c) Sky News 2026: Putin's Kremlin had possession of frog poison used to kill Alexei Navalny, foreign secretary