Russia, Navalny and the Uses of Poison in State-Sponsored Assassinations

‘We have been pursuing the truth on this since Alexei died in prison.’ In February 2026, almost two years to the day after Alexei Navalny’s death in a Russian prison, UK Foreign Secretary Yvette Cooper revealed that the Russia dissident did not die of natural causes. Based on analysis conducted by European laboratories, the France, Germany, the Netherlands, Sweden and the UK concluded that Navalny had been poisoned by the lethal toxin Epibatidine. Epibatidine is a powerful poison, produced in nature by only a few closely related South American dart frog species – but synthetic versions of this toxin have a long history in pharmaceutical research.

The European governments’ statement condemned Russia for a breach of international law and disregard of the Chemical Weapons Convention. Both Cooper and UK Shadow Foreign Secretary Priti Patel called for action against Russia. While the specifics of this call for action have, so far, remained vague, the European governments’ reaction points to the international community’s sense of repugnance towards poisons. Poisons have been and remain a particularly controversial and hideous weapon, but one states have used – and will likely continue to use – against their enemies. State use of poisons in assassinations are not likely to go away.

A Short History of Poisonings

Throughout history, elites, as well as those seeking to challenge the status quo or make personal gains, have turned to poison. There are historical records of poisoning schemes and accusations stretching back millennia, from toxic sweets and tainted wines to poison maidens – supposedly trained to seduce, lure, and kill their victims. According to a recent study by Glenn Cross and Richard Beedham, between 1945 and 2000, at least 15 states have used chemical and biological agents in the conduct of assassinations. Alongside this, one should note Russia’s use of radiological weapons. The methods of delivery have included ingestion, inhalation, injection and dermal contact.

The development and deployment of poisons has not been limited to other authoritarian or communist regimes, but has included democracies which have used poison against foreign leaders and officials in the context of decolonisation, counterinsurgency and counter-terrorism campaigns, and in efforts at regime change.

As far back as 1916, during the Mexican Punitive Expedition, US officials recruited four Japanese spies to try and assassinate Mexican revolutionary leader Pancho Villa by poisoning Villa’s coffee. Fearing assassination, Villa drank only a small amount of the poisoned coffee and survived.

Assassination attempts via poison featured in the Second World War, notably in the use by Polish resistance forces against German occupation and in the experiments of the OSS ‘Dirty Tricks Department’ under Stanley Lovell.

During the Cold War, the CIA’s poisoner in chief, Sydney Gottlieb, personally conveyed poison to CIA Chief of Station Larry Devlin in Congo. Their target was Patrice Lumumba, the first Prime Minister of independent Congo. The CIA envisaged inserting poison in Lumumba’s food or toothpaste, but lack of access foiled the plan.

One of the options considered against Dominican Republic Dictator Rafael Trujillo was a ‘pills roulette’ – mixing poison pills in with genuine pills the dictator was taking. This was abandoned due to concerns regarding access to the same pills by other family members. France used dart guns or the insertion of poison in food and drinks. In a famous case, an undercover reserve officer of the Service de Documentation Extérieure et de Contre-Espionnage (SDECE) – France’s primary intelligence service during the Cold War -put thallium in the wine and pastis of Dr. Félix-Roland Moumié, leader of Cameroon’s anticolonialist political party, the Union des Populations du Cameroun.

Israel has conducted several assassinations against Palestinians, foreign scientists and other leaders. At times, poison has been the weapon of choice, including in the botched assassination attempt of Hamas’s Khaled Mashaal, who was sprayed with a fentanyl analogue, possibly Levofentanyl.

At times, democracies have relied on poison to exploit their targets’ weaknesses and passions. In its long assassination campaign against Fidel Castro, the CIA developed poisoned cigars and a poisoned scuba diving suit. It also developed and delivered to Cuba poison pills to be inserted in Castro’s favourite drink, a chocolate milkshake. Investigative journalist Aaron Klein has alleged that Israel killed Wadi Haddad, an operative of the Popular Front for the Liberation of Palestine, with poisoned Belgian chocolates.

Authoritarian regimes have also deployed poison against dissidents and individuals they considered a threat to the regime or to the elites in power. In these cases, poison functioned as one of the many strategies of violent national and transnational repression.

Apartheid-era South Africa developed a chemical and biological weapons programs known as Project Coast which included assassination.

As Karl Dewey has detailed, Pinochet’s Chile produced chemical and biological substances, including Sarin, for military purposes, almost exclusively in applications for targeting individuals. According to some accounts, Communist Party member Alexei Jaccard Siegler, captured via the South American Operation CONDOR. While debated, Carmelo Soria, a Spanish diplomat accused of helping Chilean dissidents escape, was seemingly killed using Sarin while being tortured in prison.

Recent threats to the North Korean regime have been assassinated through poisoning. Kim Jong Nam, brother of North Korean leader Kim Jong Un, was killed using nerve agent VX at Kuala Lumpur international airport, seemingly as part of an elaborate ruse with unwitting assassins.

Poison was also defined as the regime’s weapon of choice in a recent study of Rwanda’s transnational repression, either to kill the victim or to render it powerless before assassination by other methods.

The Soviet Union (later Russia) and its Eastern Block allies have often been at the forefront of domestic and transnational assassinations. Assassinations and poisonings featured prominently in the Soviet Union’s effort to eliminate dissidents, political opponents, as well as voices critical of the regime. In the early Cold War, suspected defectors or spies, as well as prominent political figures, were killed via injection of curare and other poisons, at times while already in custody. A 1953 plot envisaged the assassination of Yugoslav leader Tito by spreading pulmonary plague bacteria in his office. It was dropped after Stalin’s death. Throughout the 1950s, several assassinations relied on ‘poison guns’, metal cylinders that delivered vaporized hydrogen cyanide. Ukrainian dissidents Lev Rebet and Stephan Bandera were famous victims.

In the assassination of Bulgarian dissident Georgi Markov, an intricate method involving a pellet-shooting umbrella was employed after earlier plots had failed. The ricin-containing pellet and the weapon were developed in a collaboration between Bulgarian and Soviet intelligence services. Ricin was found in a pellet extracted not from Markov, but from the body of Vladimir Kostov, another Bulgarian émigré who survived a similar assassination attempt.

The Soviets also used poison against troublesome foreign leaders. Afghanistan’s Hafizullah Amin was shot while lying ill in bed after he had been poisoned. A recent database, looking at post-2000 cases, found 99 assassinations conducted by Russia. Of these, about one third were poisonings. Famous examples happened on UK soil, including the assassination of Litvinenko in London and the attempt on the Sergei Skripal in Salisbury.

At times, assassination attempts via poisoning have failed, as in the case of arms manufacturer Emilian Gebrev. It should be pointed out though that, as Boris Volodarski has written, the Soviet Union and Russia also have a long history of so-called soft poisonings, aimed not necessarily at assassinating a target but at strategically and temporarily incapacitating them.

Why Poisonings?

State-sponsored assassinations, like the case of Navalny and the others detailed above, play a prominent role in international politics. Assassinations via poisonings are no different. Poisonings have traditionally been understood as having a particular set of advantages compared to other assassination methods. These included the fact that deaths might be attributed to natural causes. Poisonings allowed for the targeting of otherwise well protected individuals at reduced cost and risk to the attacker. The delayed effects of many poisons allowed for the attacker to escape before poisoning was suspected by the victim. And likewise, the threat of poisoning has often led to paranoia among those that suspected they might be targeted.

Some of these advantages have weakened in recent decades. As Dan Kaszeta has recently argued, several forensic challenges remain. However, advances in medical toxicology have made it less likely that poisonings will go unnoticed. The ability to trace movements more precisely – as both the Skripal case and the Bellingcat investigation of the Gebrev case demonstrate – makes attribution easier. Furthermore, the time elapsing between poisoning and death can permit the victim to denounce the perpetrators, as in the case of Litvinenko.

And yet, poisonings remain a potent tool of statecraft. The delayed effects of poisonings still permit the killer to escape. The delayed effects also permit the perpetrating states and other witting or unwitting actors to muddy the informational waters and sew confusion. Finally, while rumours and fears of poisoning have always followed suspicious deaths, the fall-out of such events tended to be primarily personal and local. In the modern world, the theatre where these plots unfold is much larger, and the role that poison is cast to play is much more complex – in terms of why they might be used, as well as in terms of the narrative battles which follow when an attack is discovered. This confoundment is clearly embodied in the whirling social media storms surrounding recent high-profile poisonings.

With these conflicting elements, it is no surprise that the rationale behind poisonings is strongly contested. Some scholars have looked at assassination, especially via poisoning, as a communicative device. These assassinations have a theatrical dimension. They are an effort at communicating, at signalling. An assassination sends a signal to other individuals, other dissidents, for example. It sends a signal to the domestic population regarding the strength of the regime. And it sends signals to the international community. These have to do with capabilities and arsenals of the agencies involved – something that also applies to the North Korea case. They have to do with international reach (as in the case of Litvinenko and Skripal). And they signal – as the recent statement by European governments highlighted – a disregard to rules and international law. Finally, if left without response, they signal a state’s ability to act with impunity.

Others, however, are not convinced. Kiril Avramov and other scholars, for example, have convincingly shown how the aim of assassination is – purely – to kill. In this view, assassinations aim at remaining secret. Glenn Cross, a former Deputy National Intelligence Officer for WMD & Proliferation on the US National Intelligence Council agrees. Publicity has to do with incompetence, for example mis-dosing, or unforeseen events, such as the defection of (would be) attackers. In this sense, the signalling effect is, at best a second or third order effect and, at worst, an effort at ex post facto rationalisation.

The case of Navalny reflects these controversies and complexities. Certainly, this was the second time that Navalny had been poisoned. Those looking at signalling can point to the fact that, with Navalny held prisoner in a secluded, high-security complex, there were much more obvious and straightforward means by which this could have been achieved. Means which, if discovered, would not have risked investigators making direct links to the Russian state. As some have argued, though, Navalny had a strong support team that might have had antidotes for poisons more likely found in prison. Other means, including mistreatment, might have created more visible scandals. Russia went to great length to hide the poisoning, which was only revealed via the smuggling of body samples. There may have been a belief that post-mortem investigations could be hamstringed, and Russian officials dealing with the case could be hushed up. The plan, as expert Marc Michael Blum writes, might have been that of a quiet assassination that produced samples that would never be analysed. However, we only need look back to 2018, with the Skripal case, which occurred on British soil, to realise that while there might be an element of incompetence, the avoidance of detection and association are not always primary concerns.

In this context then, while it is tempting to try and elicit some underlying rationale for the choice to use poison, we must also remember that extraordinary singular justifications are not required for decisions which have become routine. If a state has the capacity, a range of pragmatic and operation considerations, institutional interests and power dynamics affect if and how it is used.

What to do?

In terms of next steps, the West will continue to periodically bludgeon Russia’s reputation publicly. It is also clear that many western states realise allowing such actions to go unpunished risks further erosion of the longstanding global prohibition of chemical weapons – and so this issue will be raised over coming months in the context of the Organisation for the Prohibition of Chemical Weapons. In more immediate terms however, the West will be eager to shore up the means to deter future Russian outrages and will likely add to the ever-evolving raft of sanctions targeting Russia's scientific, military and intelligence organisations. Recent history also suggests that – after an initial outrage – the consequences and repercussions of assassination will be relatively minor. Finally, despite the public notoriety that the Russian state has gained through its use of poison, this is just one of many unsavoury strategies the state continues to employ.

© Brett Edwards and Luca Trenta, 2026, published by RUSI with permission of the authors.

The views expressed in this Commentary are the authors', and do not represent those of RUSI or any other institution.

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