In early December 2025, the Royal Navy found itself at the center of a high-stakes maritime drama, shadowing a Russian Kilo-class submarine, Krasnodar, and its accompanying tug, Altay, as they made their way from the North Sea through the English Channel. This meticulously coordinated three-day operation, carried out in tandem with NATO allies, underscored both the growing threat posed by Russian naval activity and the mounting strain on the United Kingdom’s own maritime defenses.
The operation was anything but routine. According to reports from the Royal Navy and corroborated by BFBS Forces News and the Daily Mail, the specialist Merlin helicopter from 814 Naval Air Squadron played a pivotal role. Embarked aboard the Royal Fleet Auxiliary (RFA) replenishment tanker Tidesurge, the Merlin crew remained on high alert, ready to pivot to anti-submarine operations if the Krasnodar submerged. Yet, despite the stormy weather—Storm Bram was lashing the UK at the time—the Russian submarine opted to stay on the surface as it transited one of the world’s busiest and most closely watched maritime corridors.
Captain James Allen, Commanding Officer of RFA Tidesurge, summed up the mood aboard: “There is nothing like a Russian submarine to focus the mind for any mariner.” He went on to praise the “teamwork and professionalism of all RFA Tidesurge ship’s company, embarked 814 Naval Air Squadron Atlantic Flight and interoperability with near regional NATO allies. We worked together as a show of presence and deterrence as we transited from the North Sea to the English Channel.”
The Royal Navy’s mission was clear: maintain an overt presence and keep a watchful eye on the Russian vessels. Lieutenant Commander David Emery, Flight Commander of 814 Naval Air Squadron’s Atlantic Flight, emphasized the stakes: “Maintaining an overt presence and continued overwatch of Russian vessels in UK waters is vital for national security. The flexibility and professionalism of the crew of RFA Tidesurge allows us to project our helicopter wherever, day or night, in the maritime environment.”
The British task force dogged the Russian submarine and its tug until they reached the northwest of France, near the island of Ushant. At that point, the shadowing responsibility was handed over to a NATO ally, reinforcing the collaborative nature of Western maritime defense. The operation’s success was a testament to NATO’s ability to coordinate across borders and respond swiftly to perceived threats in critical waterways.
This incident, however, is not an isolated one. Over the past two years, the UK government has reported a 30 percent increase in Russian vessel activity threatening British waters. The surge in Moscow’s maritime assertiveness has been a cause for growing alarm among British defense officials and their NATO counterparts. The timing of the Krasnodar’s passage—amid stormy conditions and heightened tensions—only served to amplify concerns about the Kremlin’s intentions in the region.
In the days following the operation, the conversation quickly shifted from tactical success to strategic vulnerability. General Sir Gwyn Jenkins, the highest-ranking officer in the Royal Navy, made a rare and candid admission: Britain’s defenses are “stretched.” Speaking at a naval event in Portsmouth alongside Defence Secretary John Healey, Sir Gwyn did not mince words. He acknowledged that a chronic shortage of Royal Navy submarines, coupled with budget constraints, has left the UK exposed at a time when Russian activity in the strategically vital North Atlantic is on the rise.
Sir Gwyn highlighted the troubling confluence of a lack of patrol boats and increased Russian ship activity, warning that the Kremlin views the North Atlantic as “an area of advantage for them” and is actively seeking to exploit the UK’s weaknesses. “If not challenged,” he cautioned, “Russia’s northern fleet could potentially cut off UK supply lines and threaten undersea communication as well as energy pipelines.” These pipelines, which connect the UK to Europe, Scandinavia, and North America, have become a top security priority for the British military.
Defence Secretary John Healey echoed these concerns, expressing dissatisfaction with the number of submarines the Royal Navy can currently deploy. The unveiling of unmanned vessels as part of a future hybrid fleet was meant to signal innovation, but it also underscored how stretched conventional assets have become. The message from both men was unmistakable: Britain must do more to address its maritime vulnerabilities in the face of a resurgent Russia.
The international context is equally sobering. During a visit to Berlin in December 2025, NATO Secretary General Mark Rutte issued a stark warning: “We are Russia’s next target. I fear that too many are quietly complacent. Too many don’t feel the urgency. And too many believe that time is on our side. It is not. The time for action is now.” Rutte went on to say, “Conflict is at our door. Russia has brought war back to Europe. And we must be prepared.” His remarks, delivered at the Munich Security Conference’s Berlin event, left little doubt about the seriousness with which NATO views the current threat landscape.
In response, the UK has sought to strengthen its alliances and bolster its maritime defenses. Earlier in December, London and Oslo signed the Lunna House Agreement, a major defense pact that will see the UK and Norway operate together to counter Russian undersea threats. The British Prime Minister, speaking to BFBS Forces News, declared that the UK would do “whatever is necessary to keep the country safe” in the face of these intensified threats from Russia.
For the Royal Navy’s sailors and aircrew, these developments are more than just headlines—they’re a daily reality. The operation to track the Krasnodar and Altay showcased not only the technical capabilities of the UK’s maritime forces but also the professionalism and resolve of those tasked with keeping British waters secure. Yet, as the number of Russian vessels prowling near the UK increases and Britain’s own submarine fleet faces chronic shortages, the sense of urgency is palpable.
With the North Atlantic emerging as a contested domain and undersea infrastructure more vulnerable than ever, the question facing Britain and its allies is clear: Can they adapt quickly enough to meet the challenge posed by a resurgent and increasingly assertive Russia? The events of December 2025 suggest that vigilance, cooperation, and investment in maritime security are no longer optional—they’re essential for the safety and sovereignty of the United Kingdom and its neighbors.
