Yulia Navalnaya says laboratory analyses conducted in two countries on biological samples taken from her late husband, Alexei Navalny, conclude he was poisoned while in custody in Russia.
In a video statement posted on X, Navalnaya said samples were secured in February 2024 and transferred abroad ‘by reliable means’ for testing; she urged the laboratories to publish their full toxicology findings.
We managed to transfer Alexei’s biological materials abroad. Laboratories in two different countries conducted examinations. These laboratories, independently of each other, concluded that Alexei was poisoned. These results are of public importance and must be published. We all… pic.twitter.com/Sp8w1322gY
— Yulia Navalnaya (@yulia_navalnaya) September 17, 2025
Navalny, the most prominent figure in Russia’s opposition, died on 16 February 2024 at Penal Colony IK-3 ‘Polar Wolf’ in Kharp, Yamalo-Nenets Autonomous Okrug. At the time, the regional prison service said he felt unwell after a walk and lost consciousness; officials later cited ‘sudden death syndrome’. Supporters disputed that account and demanded an independent investigation.
Navalnaya said two independent laboratories, working in different countries and without coordination, reached the same conclusion that her husband had been poisoned. She did not identify the facilities or specify the substance she believes was used, and called on the institutions involved to release their reports publicly. ‘We all deserve to know the truth,’ she said.
In her statement, Navalnaya also alleged that President Vladimir Putin bears responsibility for her husband’s death and accused Russian security services of developing prohibited chemical and biological weapons. She appealed to the laboratories’ leadership to make their data public and criticised what she described as political caution surrounding disclosure. Those assertions have not been independently verified. The Kremlin has previously denied state involvement in Navalny’s death.
Navalny previously survived a confirmed poisoning with a nerve agent from the Novichok group in August 2020. German authorities announced the finding on 2 September 2020; laboratories in France and Sweden later corroborated the result, and the Organisation for the Prohibition of Chemical Weapons (OPCW) conducted its own analyses. He was treated in Berlin and returned to Russia in January 2021, where he was arrested on arrival and later sentenced to lengthy terms on charges he said were politically motivated.
International responses to both the 2020 poisoning and Navalny’s death in 2024 included sanctions. In October 2020 the EU sanctioned six individuals and one entity, the State Research Institute of Organic Chemistry and Technology (GosNIIOKhT), in connection with the 2020 attack; the UK announced parallel measures the same day. After Navalny’s death, the EU placed additional sanctions on officials and entities linked to his detention and the penitentiary system. Russia has rejected allegations of state responsibility.
The new claim turns on the chain of custody and the integrity of the samples Navalnaya says were obtained in February 2024. She did not detail how they were collected or preserved. Navalnaya’s call for the data to be released suggests those details may emerge if the institutions agree to disclosure.
Russian authorities have maintained that Navalny died of natural causes. No official forensic report establishing a definitive cause of death has been made public. Navalny’s allies have argued that symptoms described in internal Russian documents and witness accounts are consistent with poisoning, and have repeatedly sought independent examination.
