Andrei Raevsky (The Saker) made an astute operational-strategic observation yesterday when noted that:
I can speculate about one interesting option: the real goal of these moves might be to force the Ukrainian to keep forces stationed along the coast to try prevent a Russian amphibious assault (not that I believe that any combo of Ukie forces could do that). The more forces are guarding the coast, the less forces are available for an attack on the LDNR. Also, since the Ukies (and the US+NATO) can easily track these ships, the Russian could decide to march them up and down the Ukrainian coast in order to a) keep the Ukrainian guessing where the supposed landing might be and b) to have these forces ready to support a LDNR or even Russian push towards Mariupol and further (Nikolaev, Odessa).
Now you can see how it looks like, observing how 4 Baltic and Northern Fleets' BDKs (Large Amphibious Ships) pass through Bosporus yesterday on their way to the Black Sea.
All these deployments are performed by Russia in order to remove any idiotic thoughts from whatever is running Ukraine from Kiev and make sure that they do not attempt any moves on LDNR. Some people go further and even propose that Russia, actually, has everything in place to solve Ukraine's issue once and for all. Yes, that is true, Russia has enough forces to dispose of the proto-Nazi Ukrainian state but will she? I don't know, but it is an option which people in Kiev view as not entirely improbable, so it remains active and contributes to Ukraine's strategic confusion (not that they ever resided outside this confused state), which plays in favor of LDNR.
Obviously, once mighty Albion, after Biden Admin recalled two US Navy DDGs from their Black Sea deployment, decided to show that London still matters and Royal Navy announced that it will be sending two Type 45 destroyer and Type 23 frigate to the Black Sea in an apparent show of support for Ukraine's regime:
Royal Navy warships will sail for the Black Sea next month amid rising tensions between Ukraine and Russia, The Sunday Times has reported. Citing senior naval sources, the newspaper said the deployment was intended to show solidarity with Kiev and Nato allies. One Type 45 destroyer armed with anti-aircraft missiles and an anti-submarine Type 23 frigate will leave the Royal Navy’s carrier task group in the Mediterranean and head through the Bosphorus into the Black Sea, according to the report.
Type 23 frigates are good ol' work horses of Royal Navy and are used primarily in ASW role, granted that they carry good ol' Harpoons (8 in total) and Sea Ceptor AD missiles, claimed to be able to fight off "saturation attacks" by super-sonic anti-shipping missiles. Type 45, which is much newer class of destroyers, carries the same Harpoons (8 in total) and is known as a dedicated air-defense ship carrying Aster AD complex. So, just another (European) iteration of US Navy's DDG of Arleigh Burke-class, albeit with a smaller AD missile load. Russia is trembling from fear and is sending diplomatic mail to London constantly begging for this terrifying British naval might to be recalled (wink, wink). I, personally, think that London, sending these two ships to the Black Sea, simply wants to remind everyone that it still exists and is somehow relevant to a massive geopolitical game three giants of US, China and Russia are playing. You know, glorious history, phantom pains from lost empire and greatness. Well, you get my drift. Moscow is "impressed", not.
Alexander, being a British analyst and journalist has a better insight into the British thinking. So, listen to his excellent description of British reasons.