Russia's Black Sea Fleet in Jeopardy After Ukraine Strike—U.K.

Any demonstration of Ukraine's ability to threaten the port of Novorossiysk in southern Russia is likely to place Russia's Black Sea Fleet in jeopardy, according to an assessment by Britain's defense ministry.

In its daily intelligence update on the Ukraine war, the U.K.'s defense ministry referenced an apparent attack on Novorossiysk in the Krasnodar region it says was reported by multiple Ukrainian and Russian media outlets on November 18.

Russian President Vladimir Putin
Russian President Vladimir Putin visits the destroyer Vice-Admiral Kulakov at the Naval Base of Black Sea Fleet on September 23, 2014 in Novorossiysk, Russia. Putin was forced to move his Black Sea Fleet from the annexed Crimean Peninsula to Novorossiysk in the Krasnodar region after Ukrainian attacks, the UK said. Sasha Mordovets/Getty Images

Local publications reported that an attack took place at an oil terminal in Novorossiysk port on Russia's Black Sea coast, near a major base of Russia's Black Sea Fleet.

Russian President Vladimir Putin was forced to move his Black Sea Fleet from the annexed Crimean Peninsula to Novorossiysk in the Krasnodar region after Ukrainian attacks deep into the peninsula, the British MoD previously assessed in September.

The ministry said Monday that Russian commanders will likely be concerned about threats to the Novorossiysk-based amphibious landing ship flotilla.

"These vessels are relatively vulnerable without escorts and have assumed a more important role in supplying Russian forces in Ukraine since the Kerch Bridge was damaged in October," the U.K's intelligence update noted.

It was referring to an explosion last month that caused the partial collapse of a key bridge connecting Russia to Crimea. The attack damaged an important supply route for Russia's forces. Ukrainian officials celebrated the explosion but did not claim responsibility.

The defense ministry's update noted that although full details of the Novorossiysk incident are yet to emerge, any demonstration of a Ukrainian capability to threaten Novorossiysk would "highly likely represent a further strategic challenge" for Russia's Black Sea Fleet.

"It would also further undermine Russia's already reduced maritime influence in the Black Sea," the British MoD added.

According to Ukrainian news outlet Gazeta, pro-Kremlin publications reported that a Ukrainian maritime drone attacked the Sheskharis oil hub in Novorossiysk on November 18.

However, Russia's state-run news agency Tass cited a spokesman for Russia's state-controlled oil company Transneft as saying that reports about a Ukrainian marine drone attack on the Sheskharis oil harbor were false.

"These reports do not reflect reality. There was no marine drone attack on the Sheskharis oil harbor. Hence, there is no damage to it," he said.

Ukraine claimed last week that Putin has just seven ships left in his prized Black Sea Fleet. Newsweek has been unable to independently verify the figures provided by Ukraine, but the fleet has sustained major losses since the war began in February—including the sinking of its flagship vessel, the Moskva, in April.

Newsweek has contacted Russian and Ukrainian authorities for comment.