In a first, Ukraine says it struck Russian submarine in Black Sea port with underwater drones

By Victoria Butenko, Christian Edwards, CNN

(CNN) — Ukraine’s domestic security service, the SBU, said Monday that it struck a Russian submarine in the Black Sea port of Novorossiysk, causing critical damage to the vessel and effectively disabling it.

In a statement, the SBU said the operation, which used underwater “Sub Sea Baby” drones, was the first attack of its kind. Video shared by the SBU showed a large explosion at a port.

“As a result of the explosion, the submarine suffered critical damage and was effectively put out of action,” the SBU said. CNN could not independently verify the claim.

The Kilo-class submarine is used to launch Kalibr cruise missiles, firing up to four at a time, according to the SBU statement. Russia has used the missiles throughout the war to strike Ukraine.

The agency added that the submarine is known as a “Black Hole” because of the hull’s ability to absorb sound and remain undetectable by sonar. It said that class of submarine costs around $400 million. Due to international sanctions, which have hampered Russia’s access to technological components, building a similar submarine could now cost up to $500 million, the SBU said.

Russian officials did not immediately comment on the incident.

The SBU said the vessel had been forced to remain in the port of Novorossiysk due to past successes of Ukraine’s sea drone operations, which forced Moscow to move many of its ships and submarines from Sevastopol Bay in the occupied Crimean Peninsula.

The attack Monday came amid a sustained bout of diplomacy to end Russia’s war in Ukraine. It was announced soon after the conclusion of a second day of talks between US and Ukrainian delegates in Berlin.

At a news conference Monday in Berlin, Ukrainian President Volodymyr Zelensky said that Kyiv must be “absolutely sure” about how its allies will guarantee its security before making any decisions about the front line in a potential peace settlement with Russia.

Speaking alongside German Chancellor Friedrich Merz, Zelensky said that any security guarantees should include monitoring the ceasefire.

“That is really the basis for security guarantees, because the question is: Who will carry out the monitoring? What sanctions will be applied if the monitoring missions are disrupted?” Zelensky said.

Although Zelensky said these questions have not yet been answered, Merz said the United States offered Ukraine “significant” guarantees in the talks in Berlin.

“What the US has offered here in terms of material and legal guarantees is really significant,” Merz said, without providing details.

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