On 15 December 2025, the Security Service of Ukraine (SBU) executed a ground breaking operation, deploying its indigenous "Sub Sea Baby" underwater drones to strike and disable a Russian Kilo-class attack submarine at the port of Novorossiysk in Russia's Krasnodar Region.

This marked the first recorded instance of an underwater drone neutralising a submarine in combat history, according to Alexander Kamyshin, advisor to Ukrainian President Volodymyr Zelenskyy.

Footage released by the SBU captured a dramatic explosion erupting from the water near a pier where the submarine and other vessels were docked. Reuters independently verified the location by cross-referencing the video with the port's layout and pier configurations, confirming the strike's authenticity.

Novorossiysk has emerged as Russia's primary Black Sea naval base after Moscow relocated much of its fleet from Sevastopol in occupied Crimea to evade Ukrainian strikes. The targeted diesel-electric Kilo-class submarine, one of four stationed there, boasts the capacity to carry at least four Kalibr cruise missiles—key weapons in Russia's recent barrages that have severely damaged Ukraine's power infrastructure.

Ukraine, bereft of a conventional naval fleet, has pivoted to asymmetric warfare using sea drones and missiles to challenge Russia's Black Sea dominance. This operation underscores Kyiv's growing prowess in unmanned maritime systems, forcing Russian vessels into ever more distant harbours.

Ukrainian Navy spokesperson Dmytro Pletenchuk described the strike as "another turning point" in the naval theatre of the war. He emphasised that submarines represent the most challenging targets due to their stealth and underwater mobility, yet Ukraine's drones penetrated these defences.

Repairing the damaged vessel poses acute challenges for Russia, Pletenchuk noted. Any dry-dock work would require surfacing the submarine, exposing it anew to Ukrainian surveillance and follow-on attacks—a vulnerability that complicates Moscow's logistics.

With this loss, Russia now counts three Kalibr-armed submarines remaining in Novorossiysk, diminishing its regional missile projection capabilities. The Kilo-class platforms have been pivotal in sustaining long-range strikes from the Black Sea, making their attrition strategically significant.

The timing of the attack aligns with fraught US-brokered peace talks, amid Ukrainian anxieties over potential concessions to Russia. President Donald Trump's recent assertion that Zelenskyy lacks strong "cards" in negotiations has spurred Kyiv to demonstrate its offensive reach, particularly against high-value assets like this submarine.

This strike fits into Ukraine's broader escalation of long-range operations targeting Russian oil refineries, gas facilities, power grids, and military installations. Such actions aim to erode Moscow's economic and operational resilience while compensating for disparities in conventional firepower.

Pletenchuk highlighted the operation's doctrinal implications, stating it "upends the perception of naval combat possibilities in this war." Ukraine's innovations in underwater drones signal a paradigm shift, potentially influencing global naval strategies and deterring submarine-dependent powers.

Russia has yet to issue an official statement on the incident, maintaining its characteristic reticence on battlefield setbacks in the Black Sea. However, the absence of immediate denial lends credence to Ukrainian claims, especially given prior verified losses of Russian vessels.

From a technical standpoint, the "Sub Sea Baby" drones exemplify Ukraine's rapid iteration in maritime unmanned systems. These platforms likely feature extended range, autonomous navigation, and warheads optimised for piercing hulls, enabling strikes deep into Russian-controlled waters.

Strategically, the Novorossiysk raid exposes vulnerabilities in Russia's rebasing efforts. While Crimea offered proximity to the theatre, it proved untenable; now, even southern Russian ports face credible threats, stretching naval defences thin.

For Ukraine, sustaining such operations demands continuous investment in drone production amid resource constraints. Western aid, including intelligence and components, has proven vital, though domestic ingenuity drives these breakthroughs.

Observers anticipate Russian countermeasures, such as enhanced port defences, anti-drone nets, or intensified patrols. Yet Ukraine's track record suggests adaptive tactics will persist, keeping the Black Sea a contested domain.

This event reverberates beyond the immediate tactical gain, bolstering Ukrainian morale and negotiating leverage. As peace talks unfold, Kyiv's ability to project power underwater reaffirms its resolve against capitulation.

In the wider Russo-Ukrainian conflict, naval innovations like this could redefine littoral warfare, where traditional fleets yield to swarms of expendable drones. The Novorossiysk strike thus stands as a milestone in hybrid maritime contestation.

Agencies