A Ukrainian maritime drone.Image: keystone / az
analysis
The recent negotiations in Berlin have raised hopes for peace in Ukraine. But for the Kremlin, the talks are just another theater of war.
December 17, 2025, 11:08December 17, 2025, 11:08
Martin Küper / t-online
The timing of the attack may have been coincidental, but the message was clear. While Kiev’s negotiators in Berlin had to defend themselves against Russian demands to give up the Donbass, the Ukrainian domestic secret service SBU once again demonstrated the Russian army – with a hitherto unprecedented attack on a modern submarine of the so-called Kilo class in the port of Novorossiysk.
For the first time, a submarine has been blown up with a “Sub Sea Baby”.writes the SBU. This is said to be a submersible variant of the self-developed sea drone “Sea Baby”. Ukraine used them to drive the Russian Black Sea Fleet from its main base in Sevastopol in Crimea. Even Russian warplanes have to be wary of unmanned Ukrainian watercraft, as the shooting down of a Russian Su-30 fighter jet over the Black Sea in early May showed.
Russian submarines terrorize Ukrainians
But the recent attack in Novorossiysk was not just a blow to Russian propaganda. According to British naval expert HI Sutton, the submarine that was hit is likely to be so badly damaged that it will be almost impossible to repair under wartime conditions. Especially since the naval base in Sevastopol is no longer an option for this. The explosion hit the rear part of the submarine, where sensitive parts of the diesel-electric drive and the boat’s controls are located, analyzes Sutton.
Image: t-online/dpa
For the people of Ukraine, the attack in Novorossiysk means a concrete improvement in their security. The Kilo-class submarines serve Putin’s troops as a launching pad for Kalibr cruise missiles, which Russia uses to destroy power plants in Ukraine. The younger models of the Kilo class can accommodate four of them, which, according to the SBU, also includes the submarine hit in Novorossiysk. It is said to be one of six ships of this type in service with the Black Sea Fleet, as the specialist magazine “The War Zone” reports, citing a Russian commander.
Things are getting tight for Putin’s Black Sea Fleet
After the attack, the Black Sea Fleet faces a new strategic threat. Until now, Ukraine had attacked Russian ships either with surface drones or with missiles, primarily with the self-developed Neptune anti-ship missile. The flagship Moskva was sunk in April 2022. Missiles were probably also used when Ukraine sank a Russian submarine in the port of Sevastopol for the first time at the beginning of August 2024. Now the Russians have to prepare for threats under the water’s surface – but their options are rather slim, believes naval expert Sutton.
“Russia can only lose in this situation. So far they have felt safe in the port of Novorossiysk, even after the loss of Sevastopol. Now they either have to improve their defense in Novorossiysk or move to a new base.”
Apart from the port of Ochamchire in the Russian-occupied part of Georgia, there is no longer a safe place for the Black Sea Fleet. And the harbor basin there is too small and too shallow to accommodate all the ships. «The Russians could also distribute their ships in the Black Sea, but that may make them even more vulnerable.”explains Sutton.
In Kupyansk, Zelensky disgraces the Kremlin propaganda
But Ukraine has also recently been able to harass the Russians on land, for example near Kupyansk in the Donetsk region in the east of the country. In mid-November, a Russian general claimed that the strategically important transport hub was again completely under Russian control. Shortly after the Russian attack in February 2022, Putin’s troops conquered the small town, which previously had around 30,000 inhabitants. However, in September 2022, the Ukrainians managed to liberate the city, which has been fought over ever since.
Warlord Putin recently awarded his general a medal for the alleged recapture of Kupyansk. But just three days later, Ukrainian President Zelensky suddenly appeared and recorded a video of himself in front of a city sign – an embarrassment to Russian propaganda.
Today, I am in the Kupyansk sector, with our warriors who are getting the job done for Ukraine here.
The Russians kept going on about Kupyansk – the reality speaks for itself. I visited our troops and congratulated them. Thank you to each and every warrior! I am proud of you!… pic.twitter.com/kraYEBSSai
— Volodymyr Zelenskyy / Володимир Зеленський (@ZelenskyyUa) December 12, 2025
Zelensky’s appearance was preceded by a counter-offensive by the Ukrainians that had been prepared for weeks, in which the defenders apparently succeeded in driving the Russians out of the area northwest of the city. Russian units had already advanced along the Oskil River into the center of the city.
This is what the Battle of Pokrovsk is about
According to the latest Ukrainian information, their scattered remains are said to amount to only around 200 soldiers who are dependent on supplies from drones from the air. The Ukrainians have cut off the overland route to the remaining Russian troops in the region. Russian military bloggers also describe the situation of their soldiers in Kupyansk as hopeless. Nevertheless, the Kremlin again claimed on Tuesday that its troops had completely captured Kupiansk.
The situation on the front section between Pokrovsk and Myrnohrad further south in the Donetsk region remains confusing. The Russians have been advancing there slowly but steadily for months. But Putin’s troops have not yet conquered the cities, even though Putin claimed otherwise at the beginning of December. The Ukrainians are said to have long since moved their logistics from the once important transport hub of Pokrovsk further into the hinterland. Now the remaining defenders in the city are only concerned with inflicting as many losses as possible on the advancing Russian troops.
That would be the main prize for Putin
But the war is not only raging on the battlefields in Ukraine; the warring parties are also fighting to improve their situation at a strategic level. From a Russian perspective, the most recent negotiations in Berlin are likely to serve primarily to ward off harsher Western sanctions and to tie up Europe’s diplomatic forces: Instead of putting pressure on the Kremlin with their own initiatives, Chancellor Merz and Co. will have to prevent the Western alliance from breaking up again these days.
It would be the main gain for the Kremlin if the US government could force Kiev to give up its fortress belt in the Donetsk region. But if in doubt, the Ukrainian government would rather forgo US support than give up its most important line of defense against Russia without a fight. Of course, it would also be a triumph for the Kremlin if the USA actually stopped providing Ukraine with satellite images and intelligence information. The Trump administration has briefly carried out this threat twice this year.
Expert believes collapse of the Russian state is possible
Kyiv will try to prevent this scenario. As the Wall Street Journal recently reported, the USA also provides the Ukrainians with target data for attacks deep in the Russian hinterland, for example against oil depots and refineries. The Ukrainians have been systematically and frequently attacking the Russian fossil fuel industry for months – and with increasing success.
Russian revenue from the sale of oil and gas is said to have fallen by 35 percent in November compared to the same month last year, as the Reuters news agency calculated. And Ukraine has recently expanded its attacks. While the Ukrainian attacks have so far mainly targeted facilities on the Russian mainland, Ukraine has recently also targeted ships from the Russian shadow fleet and even oil production towers in the Caspian Sea. At the same time, international customers are increasingly avoiding Russian oil in order not to become the target of Western sanctions.
So far, the Ukrainian attacks and Western sanctions have not brought the Kremlin’s war machine to its knees. But the danger for Russia is growing with every passing day, believes Eastern Europe expert Andreas Umland: “In the last few months we have seen that the Russian economy is being increasingly affected and that growing economic difficulties for Russia are on the agenda,” said Umland in a recent interview with the Center for Liberal Modernity.
“If these problems coincide with military defeats in Ukraine, the regime will collapse.”says Umland. “Then the Russian state could even collapse, just as the tsarist state collapsed in 1917 or the Soviet state collapsed in 1991. With every day of the war this scenario becomes more likely.”