The Kremlin’s Baltic Hormuz: Ukrainian attacks on Russian ports cut Russia’s gains from the Iranian oil crisis by two thirds

Ukrainian strikes on Russian maritime export infrastructure represent the most powerful blow to the Russian oil sector since the start of the full-scale war.

Unlike Kyiv’s previous attempts, the current wave is specifically targeted at the infrastructure underpinning Russia’s maritime exports of oil and petroleum products and exploits its structural vulnerabilities. Around half of all Russian oil exports and 60% of petroleum product exports still flow through Baltic ports that were originally built to supply Europe.

However, the volumes shipped via these ports cannot be diverted to the Pacific, from which oil is shipped to Asian markets. As a result, roughly 2.5 million barrels per day of crude and refined exports risk being stranded inside the country, forcing Russian oil companies to cut production. That is Kyiv's strategic objective.

If we look at crude oil export data alone, the surge in oil prices and the easing of American sanctions pushed Russian revenues to 2.3 times their December–February level during the third week of the Iran war. However, in the fourth week, Ukrainian drone strikes on Russian ports pulled revenues down by $1 billion, wiping out roughly two thirds of the previous week's gains.

The key questions now are what made the Ukrainian strikes effective and whether Russia can do anything to counter them. Its vulnerability appears to stem from the same factor that it has itself exploited in attacks on Ukrainian energy infrastructure, and that Iran is exploiting against the American-Israeli coalition: the inability of air defence systems to cope with large-scale drone attacks. If that is indeed the case, it is bad news for Moscow.

‘Kinetic sanctions’: the history of the idea

Against the backdrop of the unexpected windfall from sharply rising prices and the easing of sanctions on Russian oil, Russia now faces a new challenge in the form of sustained Ukrainian drone strikes on its oil export infrastructure.

The idea of striking at the lifeblood of Putin’s war machine, the Russian oil sector, appears to have taken shape in Kyiv as early as late 2024. At any rate, it was in the first months of 2025 that a first, rather tentative wave of Ukrainian drone strikes on Russian refineries got under way. Gabriel Collins of the Baker Institute refers to this strategy as ‘kinetic’ sanctions, contrasting them with the ‘paper sanctions’ imposed by Western countries, the effectiveness of which many consider limited (a widespread misconception, in fact: in a supply-constrained oil market, forcing a reduction in Russian volumes would simply push prices higher, offsetting the lost output).

The second wave of Ukrainian attacks on Russian oil refining capacity, which took place in the second half of 2025, was considerably more deliberate, better prepared and more sustained. Between August and December, a total of 108 strikes were carried out against Russian oil transport infrastructure, predominantly refineries and storage facilities (Re:Russia calculations; see Figure 1). The result was what might be called a contained fuel crisis in Russia, one that was nonetheless felt acutely across several regions for roughly two to three months. For instance, 21% of those surveyed said that they had encountered petrol shortages in October 2025, according to a survey by the ‘Chronicles’ project (rising to the 24% in November, per a survey by the CASE Centre). The government drew up an emergency plan to stabilise the sector (→ Re:Russia: Petrol Punch). Ultimately, by year-end, the Russian authorities had managed to bring the situation under control, drawing on surplus refining capacity, an extended ban on refined product exports, and imports from Belarusian refineries processing Russian crude.

By the end of this second attack, the Ukrainian Armed Forces began testing strikes against oil transport facilities. In November, for instance, two of the sixteen strikes on oil infrastructure targeted the marine terminal at Feodosia and the Caspian Pipeline Consortium (CPC) terminal at Novorossiysk, while two further strikes hit vessels from Russia's shadow tanker fleet off the Turkish coast in the Black Sea (the Virat and the Kairos). In December, Ukraine struck Russian oil infrastructure 18 times, with the Filanovsky oil production platform (hit twice) and the Korchagin platform, both of which export via the CPC, coming under fire for the first time. In addition, in December, Ukraine struck the Tuapse offshore oil terminal. January and February 2026 then brought a lull that, as is now clear, concealed preparations for a new strategic offensive.

The pre-war export bottleneck

From 22 March to 7 April, the Ukrainian Armed Forces carried out 10 strikes on Baltic ports (three strikes on the port of Primorsk and seven on the port of Ust-Luga), one strike on Novorossiysk, as well as strikes on the Kirish, Yaroslavl and Kstovo refineries, all of which produce goods destined for export.

Figure 1. Ukrainian strikes on Russian oil infrastructure facilities, 2025–2026

Although the exact extent of the damage remains unknown, the Ukrainian strikes caused the partial or complete suspension of port operations, and repeated waves of attacks appear to be preventing a full resumption of operations. Sergei Vakulenko, an expert at the Carnegie Berlin Centre, believes, based on an analysis of satellite imagery, that eight out of 18 storage tanks at Primorsk were hit. The loading facilities themselves were not directly struck, but oil and refined product shipments at the port were halted, most likely for safety reasons. Loading at Ust-Luga was suspended on similar grounds. The strikes hit a Novatek condensate processing plant and its tank farm, as well as a Rosneft bunkering facility used for oil transhipment and a Transneft terminal. Vakulenko estimates that at the Rosneft facility the pipeline manifold of one of the five oil-loading berths was probably damaged, along with, in all likelihood, the loading arm used to transfer refined products to tankers. Up to 12 storage tanks were damaged as a result of the strikes.

The April series of attacks additionally hit the Transneft terminal at Primorsk port (a section of the pipeline) and Transneft's Sheskharis terminal at Novorossiysk port (berth No. 2 and the pipelines serving berths No. 1 and No. 2, according to the Exelnova+ Telegram channel based on an analysis of satellite imagery), which is one of the key oil shipping hubs on the Black Sea. The port of Ust-Luga resumed oil shipments on 4 April, Bloomberg reported, but was struck again on 7 April, with the consequences as yet unknown. The port of Primorsk, sources told Reuters, remained idle as of 3 April.

The current offensive is precisely targeted at the ‘European’ infrastructure of Russian oil exports. Beyond the Druzhba pipeline, which runs through Ukrainian territory and was carrying 0.17 million barrels per day (mbd) before it was damaged in late January, the Baltic ports (Primorsk and Ust-Luga) and the Black Sea ports (Novorossiysk, Taman and Tuapse) all lie within range of Ukrainian strikes.

In January and February combined, Russia exported an average of 3.5 mbd of crude and 2.2 mbd of refined products by sea. Of that total, 48% flowed through the Baltic ports, which handled 40% of all crude exports and 60% of refined product exports, according to calculations by the ‘Shadow Fleet Tracker’ of the Kyiv School of Economics (KSE), based on Kpler data. This situation is a legacy of the pre-war era, when the bulk of Russian oil exports, and especially higher-value refined exports, were oriented towards Europe. The Black Sea ports account for a further 20% of maritime oil exports (15% of all crude oil and 30% of petroleum products). Novorossiysk, however, also serves as a transhipment point for CPC oil exports in addition to Russian crude, which considerably complicates any attack on it: strikes on consortium infrastructure draw sharp protests from the countries involved in the project. Finally, 25% of exports go through Pacific ports, consisting mainly of crude oil (35% of total crude exports) and a small proportion of petroleum products (8%). A defining characteristic of this infrastructure is its isolation: volumes of crude and refined products earmarked for Baltic shipment cannot be redirected to the Pacific ports, which lie beyond the range of Ukrainian drones and are closer to Russia's principal current customers.

The drone billion

According to widely cited estimates by Reuters, Russian oil exports fell by around 2 mbd, or roughly 40%, in late March. This approximate figure is arrived at by aggregating losses from shadow fleet tanker detentions, the halt to Druzhba pipeline flows, and port suspensions. In practice, the cumulative damage from two weeks of port strikes cannot yet be calculated with any precision; in particular, there is no up-to-date data on refined product and crude deliveries for the first week of April.

According to the International Energy Agency, in 2025, Russia exported an average of 4.8 mbd of crude in 2025 (3.5 mbd by sea and 1.3 mbd by pipeline), along with a further 2.6 mbd of refined products (2.2 mbd of which by sea). In January and February, seaborne oil exports were running at roughly the same level, with refined product exports at around 2.3 million barrels per day, according to KSE estimates. Following the onset of the Strait of Hormuz crisis and the easing of American sanctions, seaborne crude oil exports rose by 20% (compared to the start of 2026), reaching 4.1 mbd, according to Bloomberg’s calculations based on vessel tracking data. However, in the final week of March, which coincided with the first wave of attacks, they fell to 2.3 mbd, a drop of 1.8 mbd that is roughly equal to the average combined crude shipments through the Baltic and Black Sea ports over the preceding three months (1.9 million barrels per day).

However, the picture in the agency’s calculations is, if anything, even more striking, when expressed in monetary terms, as fluctuations in transport volumes are multiplied by price surges. In the second week of the war in Iran (8–15 March), Russia’s revenues from seaborne crude oil exports jumped to $2.1 billion, up from an average of $1.1 billion in the previous three months, and in the following week they nearly reached $2.5 billion, some 2.3 times higher than the average weekly revenues for December–February. However, in the final week of March, they fell by $1 billion at once, dropping to $1.44 billion, just 37% above the winter weekly average. These figures do not capture gains or losses from refined product exports. For crude alone, the losses amount to two thirds of the windfall generated by rising prices and easing sanctions in that final week of March.

Figure 2. Russian crude oil exports by sea, 2024–2026, million barrels per day

Figure 3. Russian crude oil exports by sea, 2024–2026, billion dollars per week

Thus, the Baltic ports, which account for half of Russia’s seaborne exports of oil and petroleum products, function as a kind of ‘Putin’s Strait of Hormuz’, the closure of which largely offsets the effect of blocking the actual Strait of Hormuz, controlled by the IRGC.

Should Ukrainian forces learn to target Russian terminals in Black Sea ports with similar precision, 55% of Russian oil exports and 90% of petroleum product exports would fall within their reach. This would effectively paralyse the oil export capacity of the European part of Russia, leaving Russian oil companies with nowhere to send their output. Bringing about precisely this kind of infrastructure collapse has long been Kyiv's objective, one set before the previous wave of mass strikes on Russian refineries but which proved unattainable for the reasons noted above: surplus refining capacity, rapid plant repairs, and a shift in the export mix towards crude. Between August and November 2025, refined petroleum product exports from Baltic and Black Sea ports fell significantly, whilst exports of crude oil, conversely, rose markedly. The current wave of strikes is aimed specifically at ‘trapping’ Russian oil within the country by cutting off both pipeline and maritime exports. Ukrainian analyst Evgeny Istrebin believes that the surplus of crude, including oil left unprocessed at export-oriented refineries, would reach 2.6 million barrels per day, forcing oil companies to curtail production.

The main unknown in this equation is how long Ukrainian forces will be able to keep striking the ports and prevent them from resuming normal operations. This, in turn, brings us back to the question of what has made the Ukrainian strikes so effective over the past two weeks. However, there are as yet almost no details revealing the technical aspects of the attacks. CBC News reports, based on open-source data, that all strikes on ports in the Leningrad region between 22 and 29 March were carried out not by long-range missiles, but by drones with a payload of no more than 50 kg. Some analysts, by contrast, suggest these may represent a new generation of drones with warheads of up to 100 kg. The flight paths are also under discussion, with considerable speculation that the drones cover much of their route over the Baltic states or the surface of the Baltic Sea itself.

In any case, the most likely key factor is that Ukraine now possesses a significant number of long-range UAVs that are capable of overloading Russian air defences in the European part of Russia. Moscow is forced to distribute its air defence assets across a large number of strategically sensitive directions, including the Moscow region itself. The question is therefore whether the Russian authorities can build up air defence capacity sufficient to protect the Baltic ports, first and foremost. Russia’s vulnerability appears to stem from the same factor that Russia itself has exploited in attacks on Ukrainian energy infrastructure, and which Iran is using against the US-Israeli coalition: the inability of air defence systems to cope with massed drone attacks. If that is indeed the case, it is bad news for Moscow. Whether Kyiv possesses a sufficient arsenal of heavy UAVs to sustain the pressure, however, will become clear in the weeks ahead.

Appendix. Geographical breakdown of Russian maritime exports of crude oil and petroleum products, December 2025 – February 2026