The United Kingdom is sanctioning Russian institutes accused of developing the substances used to poison Alexei Navalny.

The United Kingdom announced on Monday sanctions against two Russian research institutes and several of their senior officials, accused of being linked to Moscow's chemical weapons program and of having participated in the development of the substances used to poison Russian opposition leader Alexei Navalny.

These new measures come on the eve of the NATO summit in Ankara and follow similar sanctions adopted by the European Union.

According to the British government, these sanctions are aimed at denouncing and deterring the use of chemical weapons by Russia, which is considered a violation of international law.

In 2020, Alexei Navalny was severely poisoned during a flight in Siberia. Western laboratories concluded that he had been poisoned with a Novichok-type nerve agent, a family of chemical weapons developed during the Soviet era.

London also claims that the opposition figure died in 2024 from poisoning by epibatidine, a toxin derived from poison dart frogs, a conclusion supported by several European allies. Russia denies any involvement in his death.

The British government states that the individuals targeted by the sanctions were involved in the development of Novichok and epibatidine.

British Home Secretary Yvette Cooper denounced "Russia's repeated use of chemical weapons," which she considers a threat to international security.

She cited several cases, including the Novichok poisoning of former Russian double agent Sergei Skripal and his daughter Yulia in Salisbury in 2018, as well as that of Alexei Navalny. While the Skripals survived, the attack resulted in the death of British citizen Dawn Sturgess, who was subsequently exposed to an abandoned container of the nerve agent.

The Russian embassy in London categorically rejected the British accusations, calling them "slander." Moscow believes these allegations are being used to fuel the perception of a Russian threat in order to justify a policy of confrontation.

Last year, a British public inquiry concluded that Russian President Vladimir Putin most likely authorized the operation carried out by Russian military intelligence (GRU) agents against Sergei Skripal in Salisbury.