- The UK said Russia's Black Sea Fleet is 'functionally inactive' after Ukraine hit two of its ships.
- UK Defence Minister Grant Shapps appeared to confirm Ukraine's most recent strikes on two vessels.
- Ukraine claims to have taken out a third of Russia's navy in the waters through a series of attacks.
The UK's defense ministry declared Russia's Black Sea Fleet "functionally inactive" after Ukraine claimed to have struck another two of its ships.
UK Defence Minister Grant Shapps wrote on Sunday that Ukrainian attacks are taking a "massive" toll on the Russian fleet, in a post that appeared to confirm a pair of strikes Ukraine announced on Sunday.
"Russia has sailed the Black Sea since 1783 but is now forced to constrain its fleet to port," Shapps wrote. "And even there Putin's ships are sinking!"
Earlier on Sunday, Ukraine announced that it had struck two large landing vessels in the port of Sevastopol, in Crimea. Some sources said the missiles used to hit the Yamal and Azov were likely UK-supplied Storm Shadow cruise missiles.
The Yamal sustained critical damage to part of its upper deck and is taking on water, Ukraine's Defense Intelligence claimed on Monday.
A communications center and several infrastructure buildings in Sevastopol were also hit, the General Staff of Ukraine's armed forces said.
The extent of the damage to the Azov is not immediately clear.
According to The Telegraph, each ship would cost about $215 million to replace with modern equivalents.
The strikes are the latest in a long string of Ukrainian attacks that have significantly curtailed Russia's naval activity in the Black Sea.
Ukraine has used both cruise missiles and naval drones to harass ships at Sevastopol, the most well-equipped port in those waters.
One of the most eye-catching attacks was the sinking of the Ivanovets using home-developed MAGURA V5 naval drones in January.
Ukrainian officials said that as of February Russia had lost a third of its fleet to the attacks.
Not all of the attacks have been confirmed, but their sheer number is impressive considering Ukraine has no functioning navy of its own.
Last fall, after a major attack on Sevastopol, Russia moved much of its Black Sea Fleet to safer ports, such as Novorossiysk and Fedosia — a move that James Heappey, a UK defense minister, said signaled the "functional defeat" of the Black Sea Fleet.
Onlookers have been skeptical of such pronouncements. Even from those ports, Russia's fleet is still able to fire long-range missiles and lay mines.
Even so, it made the waters safe enough for Ukraine to open an active trade route, while continuing to pound Russia's navy.