The NATO is increasing its activities in the Black Sea [reconnaissance flights and presence of military vessels] because the US wishes to provoke an incident between NATO and Russia, similar to the provocation that took place in Kerch. The US wants to provoke a violent Russian response in order to block rapprochement between Russia and Turkey and to undermine the Turkish stream natural gas pipeline project.
The latest major provocation organised by Kiev took place on November 25, when three ships of the Ukrainian Navy violated the Russian border near the Kerch Strait. They were conducting dangerous manoeuvrers and refusing to obey orders from the Coast Guard before attempting illegal actions in Russian territorial waters. The Russian coastguard then used weapons to stop them. Russian authorities arrested 24 Ukrainian soldiers, including two members of the Ukrainian Security Service (SBU). These agents were on board the ships to coordinate the provocation.
Russia condemns the intense activity of NATO in the Black Sea and will take appropriate and adequate measures to neutralise the dangers resulting from a growing NATO activity.
A continuation of the pro-Kremlin narrative that, on November 24th 2018, Ukrainian ships approached the Kerch Strait without giving any warning, leading the Russian side to open fire.
The use of the Kerch Strait and the Sea of Azov is regulated by a bilateral treaty between Russia and Ukraine, signed in 2003 and ratified by Russia in 2004. According to the document, the Sea of Azov is considered to be the “internal waters” of both Russia and Ukraine.
According to a Bellingcat investigation based on geolocated video footage, Ukrainian ships did enter Russian-claimed territorial waters. They are, in fact, only Russian-claimed territorial waters, rather than internationally recognised boundaries.
Based on information provided by the Russian FSB, the shooting of the ‘Berdyansk’ ship (the most serious incident) most likely took place in international waters. For further details about the incident, see the Bellingcat investigation.
As stated by NATO heads of state and government at the Warsaw Summit in July 2016, "the Alliance does not seek confrontation and poses no threat to Russia. But we cannot and will not compromise on the principles on which our Alliance and security in Europe and North America rest".