Ukrainian vessels entered Russian territorial waters, the waters that were Russian even before Crimea has joined the Russian Federation.
Summary
Ukraine’s provocation in the Kerch Strait derailed the planned Putin-Trump meeting.
Disproof
On November 25 border patrol boats belonging to Russia’s FSB security service seized two small Ukrainian armoured artillery vessels and their crews after shooting at them, wounding several Ukrainian servicemen. Russia argued that they were in Russian waters.
However a bilateral treaty between Russia and Ukraine, signed in 2003 and ratified by Russia in 2004, governs the use of the Kerch strait and the Sea of Azov, which in the treaty is considered to be the “internal waters” of both Russia and Ukraine.
The construction of the Kerch Bridge took place without Ukraine's consent and constitutes a violation of Ukraine's sovereignty and territorial integrity. It has led, in parallel with the militarisation of the Azov Sea, to tougher controls on naval traffic in the strait. The European Union stated that it expects Russia to stop the inspections.
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