International Tribunal for the Law of the Sea (ITLOS) has no jurisdiction over the Kerch Strait dispute. The tribunal has no jurisdiction either over naval vessels nor warships.
This is one of the narratives promoted by the pro-Kremlin disinformation campaign on Azov sea and the Kerch Strait incident.
The UN Convention on the Law of the Sea ratified by Russia in 1997 and Ukraine in 1999 regulates the legal order for the seas and oceans. The International Tribunal for the Law of the Sea (ITLOS) was established in 1996 on the basis of the Convention. According to Article 288 of the Convention, the tribunal shall have jurisdiction over any dispute concerning the interpretation or application of this Convention. In its April 16 2019 decision the tribunal ruled that it has jurisdiction over the Kerch Strait dispute.
According to Article 298 of the UN Convention, the state has the right not to recognize the tribunal’s jurisdiction over the disputes concerning military activities. This provision, however, refers to military activities rather than warships, as claimed.
ITLOS ruled on May 25 after deliberation that the Russian Federation shall immediately release the Ukrainian naval vessels and detained servicemen.
On November 25th, 2018, border patrol boats belonging to Russia’s FSB security service seized two small Ukrainian armoured artillery vessels and a tug boat 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 are considered to be the “internal waters” of both Russia and Ukraine.