Cars stand in line for gasoline at a Lukoil gas station on July 8, 2026 in Nakhabino outside of Moscow, Russia. Russian cities are experiencing a shortage of automobile fuel caused by numerous Ukrainian drone attacks on oil refineries.

Contributor | Getty Images News | Getty Images

Ukraine has stepped up its attacks on Russian fuel tankers in the Sea of Azov, seeking to disrupt supplies to occupied Crimea at a time when drone strikes have triggered nationwide gasoline shortages.

Ukraine's drone force commander Robert Brovdi, known as Magyar, said via Telegram that 14 Russian ships were hit in the Sea of Azov on Thursday evening, taking the number of Russian stuck by Ukrainian drones to 35 over the last 96 hours. CNBC could not independently verify this report.

The drone strikes form part of Ukraine's campaign designed to choke off supplies and transportation routes in and out of Crimea, which Russia seized by force in 2014.

Situated off the southern shores of both Ukraine and Russia, the Sea of Azov is a shallow inland sea that sits to the northeast of the Crimean peninsula.

Defense experts and strategists have described Ukraine's drone attacks as pivotal in helping to stall Russia's military momentum, while also warning that Kyiv's deep-strike successes have drastically raised the risk of escalation.

Ukraine has frequently targeted high-profile oil refineries in major cities such as Moscow and St. Petersburg in recent weeks as part of a sustained push to cut off Russia's energy revenues.

Read more

Earlier this week, Ukraine marked what appeared to be one of the country's deepest attacks on Russian territory in the war so far.

Plumes of black smoke were seen billowing from a key oil refinery in the city of Omsk on Tuesday, prompting Ukrainian President Volodymyr Zelenskyy to declare that the country's upgraded drone capabilities have put Siberia "within reach."

The Omsk facility is situated nearly 2,500 kilometers (1,553 miles) from Ukrainian territory and close to Russia's border with Kazakhstan.

Long queues have been seen at Russian petrol stations as the country grapples with a worsening fuel crisis. Indeed, Russian President Vladimir Putin recently acknowledged the impact of Ukrainian drone strikes on Russian fuel production for the first time.

Holger Schmieding, chief economist at Berenberg, said the "costs of war are mounting" for the Kremlin.

Russian gross domestic product (GDP) growth stalled in the first quarter, according to official data, following a sharp slowdown last year and a temporary boost from surging military spending in 2024 and 2023.

A man refuels a car at a Gazpromneft petrol station in Moscow on June 24, 2026.

Igor Ivanko | Afp | Getty Images

"While the private sector seems to be contracting due to labour shortages, a scarcity of some materials and high interest rates, the military sector continues to thrive," Schmieding said in a research note published Friday.

"Unless the Strait of Hormuz is closed again for a sustained period of time, sending energy prices and Russian export proceeds skywards, Russia's economic and fiscal situation will likely worsen significantly further," he added.