MoonOfAlabama reported on the HMS Defender incursion into limited waters around Crimea. He has published an updated report. I shall try to summarize these reports and others and include some significant events happening before and after to place the event in context.
RT summarized the event as follows:
According to Russia’s Ministry of Defense, the British naval ship entered the country's territorial waters at 11:52am local time and traveled 3km inside the frontier, near Cape Fiolent, in Crimea. The peninsula is not recognized by the United Kingdom as Russian land and London believes it to be illegally occupied Ukrainian territory.
“At 12:06 and 12:08, a border patrol ship fired warning shots,” the Defense Ministry said. “(And) at 12:19, a Su-24m aircraft performed a warning bombing (4 OFAB-250) ahead of the course of the USS (*) Defender.”
Four minutes later, at 12:23, the destroyer left Russian territory.
(*) I presume this is a deliberate or accidental mistype. Its HMS Defender not USS Defender.
The UK MoD blathers about "innocent passage" and "no shots were fired AT" the ship, which proves that they understand the targeting of warning shots.
The Russian MoD calls their bluff releasing video (sources) showing two coast guard ships engaging the HMS Defender and informing them to change course to starboard (right), and that they'll fire if action is not taken. This is a very interesting video as it shows a close up of a coast guard vessel's navigation system, thus showing position and date and time.
Reports are that there were 20 odd Russian military planes above, some of which are viewable in the Russian MoD video and others of which can be heard in the on board BBC reporter’s audio report.
There can be no doubt that the Russians were rather annoyed.
Preceding Events
Apart from the USA/Russia summit in Geneva in which USA President Biden was seeking "stable and predictable" relations between the two nations, there had also been the event of the UK Foreign Minister Raab calling his Russian counterpart Lavrov during which Mercouris reports (see sources) that Raab gets his ears chewed off, based on a transcript from the Russian Foreign Ministry.
Soon after the UK proposes (see sources) a summit with Russia.
Just a day or two ago the UK paper The Telegraph reported that Raab having learned of the intended "innocent passage" warned that this could play into the Russian's hands. The intended action was escalated to the UK Prime Minister Johnson for a final decision, and it was obviously approved.
Some weeks prior to all of this the Russian Federation had issued a Notice to Mariners which temporarily revoked "innocent passage" for all foreign warships or government vessels. An analysis of the legality of this by a Professor of International Law was dug up by MoonOfAlabama. It is not "legalese" and very readable, and of course complete in relevant detail and highly precise in language and quotation. The TL;DR version is if Crimea is a part of Russia they can do this. If you consider Russia an occupying power then they can also do this. It could also be noted that the Notice to Mariners was issued the day before the expected arrival of two USA warships in the Black Sea, which the USA aborted.
Apart from the Notice to Mariners mechanism used by Russia to legally enforce the temporary removal of “innocent passage” for foreign government ships, and especially military vessels, Craig Murray, a former diplomat and someone quite familiar with the Laws of the Sea made other criticisms of the course instructed upon HMS Defender.
Russia appears to have precisely complied with the relevant international treaties and laws, whereas the UK political leadership has instructed their destroyer to flout them. One could even accuse the UK political leadership of putting its own citizens, both civilian and military, at deliberate risk.
To top it all off, on the same ship, hours before the UK and Ukraine had signed agreements to enhance Ukrainian naval capacity. This seems to be based on a loan which had been agreed a few months earlier, which is about maintaining British shipbuilding capacity and its military arms trade.
Following/Upcoming Events
French President Macron and German Chancellor Merkel call for Putin to be invited to an EU summit. The Dutch, Poles and Baltic states are resistant.
Exercise SeaBreeze (see sources) is due to start in days involving the USA 6th Fleet among 30 odd nations in or around the Black Sea. The “30 odd” seems like “massaging the truth”. What are South Korea, Australia or Sweden going to do in the Black Sea? “Observer on deck” or watching the live Zoom feed?
Analysis
It seems obvious that the actions of HMS Defender were patently provocative and that Russia as a sovereign or occupying power has every right to limit access within the territorial waters in the way they have.
Raab seems to have learnt a little from Lavrov during their discussions. Raising his concerns about the incursion was appropriate. But, this event seems to have had high level political support, hence the stationing of a BBC reporter on the HMS Defender. It was designed to achieve widespread media coverage.
Additionally, MoonOfAlabma's original piece identifies a USA surveillance plane tracking the incident. Unsurprisingly, the USA are interested in learning of Russia standard response patterns to an incursion. I suggest that the plans for the incursion are from NATO and this was the purpose, with the UK deciding to create a media event from it which they hoped would put Russia in a negative light. They have completely bungled both the concept and the incident response, so no joy for them, but USA/NATO does get detailed standard response data from Russia.
It is not too hard to predict that any UK/Russia summit is in the dustbin and that USA/French/German diplomats will be informing the UK to knock it off. Get back to your ship building.
Sources
These Uppity Brits Need A Slap-like Lesson, MoonOfAlabama
Experts: British HMS Defender Stunt Near Crimea Was Patently Illegal, MoonOfAlabama
Срочно | ФСБ показала стрельбу по английскому эсминцу | Британцы врали | Соловьёв LIVE (VGTRK a Russian public broadcaster)
Exclusive: Dominic Raab warned MoD about Royal Navy's Crimea plans, The Telegraph
Warmongering British Actions in the Black Sea, Craig Murray
Germany mistakenly considers Russia’s restrictions on navigation of warships in the Black Sea to be “very problematic” and, in part, “contrary to international law”, Prof. Dr. Stefan Talmon LL.M. M.A
UK signs agreement to support enhancement of Ukrainian naval capabilities, Conservative Post (UK)
Babcock signs tripartite agreement to support enhancement of Ukrainian naval capabilities, Ukrainian Military Pages
loan, Naval Technology
Russia's Lavrov Chews UP UK's Raab in Fiery Call, Alexander Mercouris
London Floats Putin-Johnson Summit, Alexander Mercouris
EU Splits on Russia As Merkel and Macron Want Talks With Putin, Alexander Mercouris
Exercise SeaBreeze 2021