After the adoption of UNCLOS, the single case of comprehensive sovereignty
and not of jurisdictional competences, in a specific maritime zone is the territorial
sea, which extends seaward up to 12 nm from the coastal states’ baselines. In fact,
UNCLOS Art. 2 (1) posits that “the sovereignty of a coastal State extends, beyond its
land territory and internal waters to an adjacent belt of sea, described as the territorial
sea”. In addition to the waters, coastal states also exercise sovereignty over the air
space and the seabed within the 12 nm. That same treatment applies to archipelagic
states, whose sovereignty extends to the waters enclosed by the archipelagic baselines, regardless of their depth and distance from the coast.
59 Even in the territorial
sea (or archipelagic waters), however, coastal states have their sovereignties
restricted, from the moment they are obliged to observe the fundamental right of
innocent passage, inasmuch as the passage be truly innocent.
60
Even though coastal states’ sovereignty over their territorial sea is reassured in
various parts of UNCLOS, as in Art. 211 (4),
61 it would be technically wrong to refer
to that ensemble of powers exercisable by the coastal states over the territorial sea as
“full sovereignty” (in contrast with lighter variants exercised in maritime zones
farther away offshore, such as the contiguous zone, the EEZ or the continental
shelf). As seen above, sovereignty over the territorial sea is limited in certain
occasions, what prevent one from asserting “full sovereignty”.
62 That kind of
complete and plain power is exercisable only over the internal waters and port
facilities of the coastal state, which receive the same legal treatment of the land
territory.
63 Overall, the Convention explicitly recognizes the sovereignty of coastal
state over the territorial waters, but does impose limits in the exercise of that
sovereignty, for the sake of safeguarding navigational rights, without which international maritime trade would be at risk.
59 Article 49 (1) UNCLOS.
60 The passage of a foreign vessel through the territorial sea shall be expeditious and continuous, and
not prejudicial to the peace, good order and security of the coastal state. UNCLOS Articles 18 and
19. Overall, UNCLOS is coherent in prohibiting any foreign vessel of engaging in activities within
the territorial sea that may be regarded as a threat against the sovereignty of coastal states and states
bordering international straits. See also UNCLOS Article 39 (1), on the duties of ships and aircraft
during transit passage through an international strait.
61 Article 211 (4) UNCLOS, according to which coastal States may, “in the exercise of their
sovereignty within their territorial sea, adopt laws and regulations for the prevention, reduction
and control of marine pollution from foreign vessels”.
62 UNCLOS mentions “full sovereignty” solely in reference to the powers of transit states over their
land territory, in cases where freedom of transit exists between a land-locked state and a transit state.
See UNCLOS, Article 125 (3).
63 UNCLOS, Article 8, on internal waters.
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4 Sovereignty and Jurisdiction in the Law of the Sea
and not of jurisdictional competences, in a specific maritime zone is the territorial
sea, which extends seaward up to 12 nm from the coastal states’ baselines. In fact,
UNCLOS Art. 2 (1) posits that “the sovereignty of a coastal State extends, beyond its
land territory and internal waters to an adjacent belt of sea, described as the territorial
sea”. In addition to the waters, coastal states also exercise sovereignty over the air
space and the seabed within the 12 nm. That same treatment applies to archipelagic
states, whose sovereignty extends to the waters enclosed by the archipelagic baselines, regardless of their depth and distance from the coast.
59 Even in the territorial
sea (or archipelagic waters), however, coastal states have their sovereignties
restricted, from the moment they are obliged to observe the fundamental right of
innocent passage, inasmuch as the passage be truly innocent.
60
Even though coastal states’ sovereignty over their territorial sea is reassured in
various parts of UNCLOS, as in Art. 211 (4),
61 it would be technically wrong to refer
to that ensemble of powers exercisable by the coastal states over the territorial sea as
“full sovereignty” (in contrast with lighter variants exercised in maritime zones
farther away offshore, such as the contiguous zone, the EEZ or the continental
shelf). As seen above, sovereignty over the territorial sea is limited in certain
occasions, what prevent one from asserting “full sovereignty”.
62 That kind of
complete and plain power is exercisable only over the internal waters and port
facilities of the coastal state, which receive the same legal treatment of the land
territory.
63 Overall, the Convention explicitly recognizes the sovereignty of coastal
state over the territorial waters, but does impose limits in the exercise of that
sovereignty, for the sake of safeguarding navigational rights, without which international maritime trade would be at risk.
59 Article 49 (1) UNCLOS.
60 The passage of a foreign vessel through the territorial sea shall be expeditious and continuous, and
not prejudicial to the peace, good order and security of the coastal state. UNCLOS Articles 18 and
19. Overall, UNCLOS is coherent in prohibiting any foreign vessel of engaging in activities within
the territorial sea that may be regarded as a threat against the sovereignty of coastal states and states
bordering international straits. See also UNCLOS Article 39 (1), on the duties of ships and aircraft
during transit passage through an international strait.
61 Article 211 (4) UNCLOS, according to which coastal States may, “in the exercise of their
sovereignty within their territorial sea, adopt laws and regulations for the prevention, reduction
and control of marine pollution from foreign vessels”.
62 UNCLOS mentions “full sovereignty” solely in reference to the powers of transit states over their
land territory, in cases where freedom of transit exists between a land-locked state and a transit state.
See UNCLOS, Article 125 (3).
63 UNCLOS, Article 8, on internal waters.
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4 Sovereignty and Jurisdiction in the Law of the Sea