UNCLOS Article 18 defines "passage" as navigation through the territorial sea without entering the internal waters of the coastal State or for the purpose of entering or leaving the internal waters, with the condition that the passage be continu- ous and expeditious, save in cases incidental to navigation, of force majeure, distress, or for rendering assistance to other ves- sels.3 ' UNCLOS defines "innocent passage" in Article 19(1) as "innocent so long as it is not prejudicial to the peace, good order or security of the coastal State."
Article 19 lists activities that constitute a threat to the peace and security of the coastal State, and are therefore pro- hibited in the territorial sea. Those activities are: 1. military activities; 2. activities contrary to the coastal State's customs, fiscal, immigration or sanitary regulations; 3. pollution; 4. fish- ing activities; 5. research or survey activities; 6. interference with systems of communication or any other facilities or instal- lations; and 7. "any other activity not having a direct bearing on passage."32 Article 20 also imposes on foreign submarines and other underwater vehicles the obligation to navigate on the sur- face and show their flags while in the territorial sea of another State.
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The Ukrainian warships had
intelligence officers on board and therefore violated condition 1 of 'innocent passage'.
They also failed to heed the instructions of the coastal state (Russia) when in Russian waters.
Two violations of UNCLOS relating to inland sea rules.