Since Russia’s full-scale invasion of Ukraine in February 2022, Vladimir Putin’s regime has resorted increasingly to grey zone warfare tactics to undermine the EU’s will and ability to support Kyiv. This means that actions to cause disruption and anxiety across political Western Europe are on the rise, as Moscow attempts to achieve its goals in a shadow campaign, away from the missiles and drones which attack Ukraine on a regular basis. 

There is no doubt that Vladimir Putin’s decision to launch a large, conventional invasion of neighbouring Ukraine in the early hours of 24th February 2022 ushered in a new era of geopolitics in Europe, but what has gone relatively unnoticed in the general media is the escalating shadow campaign against the rest of the continent by Russia, which appears to be gathering pace with each passing year. While Russian and Ukrainian forces remain largely locked in a brutal war along their frontline with long-range strikes increasing into Russia and across Ukraine , Moscow has spent the last few years also pursuing a quieter, more insidious strategy called grey zone warfare. This has been defined by former US Deputy Secretary of Defence Robert Work as the use of ‘deception, infiltration and persistent denial’ to further a country’s geopolitical aims (Robinson 2023). This is achieved by frustrating the opponent’s ability to counteract the secretive nature of operations. (Cancian and Monaghan 2023) reference a report from U.S. intelligence that Russia’s losses in Ukraine mean that Moscow ‘less capable of posing a conventional military threat’. This sub-threshold domain, therefore, has grown in importance to represent a key contemporary factor in Russia’s activities.

In the context of the Russo-Ukrainian War and the profound geopolitical shifts which have occurred in the aftermath, grey zone tactics play a significant role in analysing Russia’s intentions for Europe, both in the short- and long-term. In the four years following the invasion, Western countries have generally stepped up to provide an impressive amount of military support to Kyiv, by transferring HIMARS (rocket artillery system) and Patriot air defence units, among other sophisticated hardware transferred to Ukraine. European states have been providing an increasingly critical amount of support, notably with Britain’s Challenger 2 tanks which formed the first shipment of tanks to support the Ukrainian war effort. It is in Russia’s clear interest to prevent Western equipment reaching the Ukrainian military, which continues to adeptly deny Russia a clear and easy advance through Ukraine’s eastern territory. Moscow, however, cannot directly strike the depots in Poland which coordinate these weapons transfers, as a Russian strike on NATO territory with civilian and/or NATO losses would almost certainly trigger Article 5. This is NATO’s mutual defence clause, where an attack on one member constitutes an attack on all, to encourage a collective response. This is where grey zone tactics play a major role; Russia can, and does, attempt to disrupt and degrade Western support for Ukraine in an indirect manner. This has been described as a ‘low-risk, high-impact’ method to raise costs for Western countries through a psychological campaign which also threatens economically (Ince 2025). 

This can take the form of financially recruiting citizens in the West to play their own role in attacking sites linked to the military-industrial sphere, which is the system by which weapons are procured and then sent to Ukraine. (Sandford and Rhoden-Paul 2025) report that last October six British nationals were charged in connection with an arson attack on a London depot in 2024, targeting a facility which provided military aid to Ukraine. In this case, the Russian mercenary group Wagner provided the men with instructions, confirming that officials based in Russia chose the depot as a target. This represents a classic example of grey zone warfare, with relatively smaller actions designed at damaging the enemy’s material conditions, conducted by agents on behalf of a hostile power. By demonstrating a willingness to incur costs on Western support for Kyiv, this campaign can be understood as an attempt to coercively change the policy of supplying material to Ukraine.

Meanwhile, many analysts agree that the year 2025 saw an escalation of Russia’s grey zone tactics, perhaps signalling that Moscow views this realm as a long-term strategic focus. Vitally, it appears as though Russia is expanding its grey zone operations to gauge the West’s resolve to defend ‘every inch of NATO territory’ as former U.S. President Joe Biden famously stated immediately after the invasion of Ukraine. Last September, for example, Russian aircraft entered Estonian airspace for around 12 minutes, before withdrawing as NATO deployed aerial assets to respond to the incursion. This occurred during a period of increased Russian hybrid activity against the region. The Baltic States lie on the eastern edge of NATO and directly border Russia and/or its ally Belarus. Therefore, many observers indicate that Russia is purposefully testing the weight of Western responses in order to judge the extent to which NATO may be willing to militarily intervene to defend its Eastern Flank. This incident again classically represents the logic and practice of grey zone operations; instead of conducting a large-scale operation to draw a large response, Moscow decided to deploy a light force to probe the counter-response, as it seeks to increase the scope of its activities.  In order to enhance the effectiveness of its hybrid campaign, Russia has actively increased its defence posture; area-denial capabilities have improved with Russian strategic bombers able to challenge NATO force projection which is crucial to repelling a hostile incursion (Elonheimo 2022).

 A separate railway sabotage incident late last year, aimed at disrupting access to the Polish-Ukrainian border, thankfully avoided civilian casualties when a train driver noticed unusual signs on the track. The possibility of civilian harm meanwhile demonstrates Russia’s increasingly brazen activities, in risking casualties more widely. What is also important to note is that 2025 saw the media begin to refer to these events as a deliberate Russian effort for the first time, improving the public’s knowledge of Russia’s hostile actions which stand to test the West. According to (Oǧuz 2016), Russia has proven ‘remarkably effective’ in using non-military methods to ‘disable international responses’; a key aspect of this is Moscow’s plausible deniability through its diplomatic networks. This is especially important at a time when online disinformation is playing a huge role in fostering false narratives online concerning Russia’s War in Ukraine, aimed at undermining faith in the establishment and to open the way for Russian-influenced narratives to take hold. Transparent media recognition is crucial in countering these narratives, not least because they rely on a lack of popular awareness to win acceptability.

Moreover, it has been argued that the term ‘grey zone warfare’ is unhelpful as it ignores the long history of deception in conflict, adding that it encourages complacency by suggesting the West is unable to recognise these actions and to appropriately respond. In the case of the Russian annexation of Crimea in 2014, part of a wider campaign by Putin, the West’s relatively lukewarm response encouraged Russia’s actions by refusing to define the event as the pre-meditated aggression that it was. Although Putin aimed to keep a degree of deniability, it was an open secret that the order for the military operation came from the highest levels of the Kremlin (Treisman 2016). Therefore, it is sometimes argued that grey zone warfare is a term used in the West to disguise a more long-term information campaign pursued in geopolitics. During the Cold War, both the West and the Soviet Union sought to weaponise information against the other and broadcast damaging narratives to weaken the other’s position, so in this instance, disinformation as a tactic is not new. 

To conclude, therefore, it seems that grey zone tactics will remain part of Russia’s arsenal against the West, as it attempts to sow discord across much of Europe, both to destabilise the liberal democracy which largely defines the EU and to degrade the levels of support for Ukraine in practical terms, including targeting weapons shipments for Kyiv. With the Trump administration’s lukewarm opinion both of Ukraine and Europe as a whole encouraging Russia, it remains to be seen whether NATO countries, specifically larger powers including the UK and France, will adopt a counter-strategy to respond to and deter Russian grey zone tactics. With the war in Ukraine not likely to end soon, this remains an increasingly important area for the West to exercise its collective power.

Bibliography

Cancian, Mark F, and Sean Monaghan. 2023. “Threats to Baltic Security.” “Repel, Don’t Expel.” Center for Strategic and International Studies (CSIS). JSTOR.

Elonheimo, Tuukka. 2021. “Comprehensive Security Approach in Response to Russian Hybrid Warfare.” Strategic Studies Quarterly 15 (3): 113–37. 

Ince, Matt. 2025. “Maintaining the UK’s Intelligence Edge in the Grey Zone.” Rusi.org. 2025. 

OĞUZ, ŞAFAK. 2016. “Prepared for Russian Hybrid Warfare?” Insight Turkey 18 (4): 165–80. 

Robinson, Clay. 2023. “Protect Unmanned Surface Vessels in the Gray Zone.” U.S. Naval Institute. January 25, 2023.

Sandford, Daniel, and Andre Rhoden-Paul. 2025. “Men Jailed over Arson Attack for Russia on Ukrainian Business in London.” BBC News, October 24, 2025. 

The Military Balance 2026: Fortifying NATO’s Eastern Flank.” 2026. IISS. 2026. Treisman, Daniel. 2016. “Why Putin Took Crimea: The Gambler in the Kremlin.” Foreign Affairs 95 (3): 47–54.