Sea is a large body of water that is surrounded by the land. It is an important a part of human trade and commerce, voyage, mineral processing, power generation and is additionally considered as an important source of blue economy nowadays. International law of the ocean may be a law of maritime space that peacefully settles the worldwide disputes on maritime boundary between or among the States and defines various jurisdictions of the maritime zones also because the rights and obligations of the coastal States in these zones, especially with reference to the conservation of marine environment and biodiversity.

Territorial sea is that part of the sea which is adjoining to the coastal State and which is adjacent to the high seas on its outer boundary. The Coastal State exercises its supremacy over this area as it exercises over its domestic waters. The sovereignty expands to the airspace over the territorial sea as well as its bed and sub-soil. This sovereignty accumulates to a State under the customary international law which no State can rebut.

Law of the Sea

The law of the ocean may be a body of customs, treaties, and global agreements; by which governments maintain order, productivity, and amicable relations on the ocean. It involves subjects such as navigational rights, sea mineral claims, and coastal waters jurisdiction.

Body of international law concerned with civic order at sea. Much of this law is codified within the United Nations Convention on the Law of the ocean, signed Dec. 10, 1982. The convention, described as a “constitution for the oceans,” represents an endeavor to systemize international law regarding territorial waters, sea-lanes and ocean resources. It came into authority in 1994 after it had been approved by the required 60 countries; by the early 21st century the convention had been approved by 150+ countries.

UN Convention of the Law of the Sea

Maritime zones are a principal component of present law of the sea. The first effort to publish and codify a comprehensive law of the sea was in the 1950s, shortly after the Truman proclamation on the continental shelf. In 1956, the United Nations held its first Conference on the Law of the Sea (UNCLOS I) in Geneva, Switzerland, outcome of which was four treaties concluded in 1958: Convention on the Territorial Sea and Contiguous Zone, entry into force: 10 September 1964 Convention on the ocean floor, entry into force: 10 June 1964 Convention on the High Seas, entry into force: 30 September 1962 Convention on Fishing and Conservation of Living Resources of the High Seas, entry into force: 20 March 1966

The Convention on the ocean floor effectively codified Truman’s proclamation as customary law of nations. While UNCLOS I was widely considered a triumph, it left unwrap the concern of the extent of territorial waters. In 1960, the UN held a second Conference on the Law of the Sea (“UNCLOS II”), but this did not result in any new agreements. The pressing issue of varying claims of territorial waters was elevated at the UN in 1967 by Malta, prompting in 1973 a third United Nations Conference on the Law of the Sea in New York City. In an effort to scale back the likelihood of groups of nation-states dominating the negotiations, the conference used a consensus process instead of majority vote. With quite 160 nations participating, the conference lasted until 1982, leading to the UN Convention of the Law of the ocean, also referred to as the Law of the Sea Treaty, which defines the rights and responsibilities of nations in their use of the world’s ocean.

Territorial Sea

Maritime Belt or territorial waters is that belt of the sea which is adjacent to the costal state and over which costal state exercises the sovereignty. The territorial sea (also called territorial waters) may be a maritime area beyond and adjacent to the interior waters, and shall not extend beyond twelve nautical miles (‘nm’) from the baselines. In the territorial sea the coastal State exercises sovereignty extending to the air space over the territorial sea also on its bed and subsoil.[1]

However, the sovereignty over this zone has to be exercised subject to the provisions of the conventions and ‘to other rules of international law’ which provides several rights to other States, particularly right of ‘innocent passage’ within the body of water of the State. The territorial sea extends to a limit of 12 nautical miles from the baseline of a coastal State. Within this zone, the coastal State exercises full sovereignty over the air space above the sea and over the seabed and subsoil. A coastal State may enact on matters concerning the security of navigation, the preservation of the environment, and the prevention, reduction, and control of pollution without any compulsion to make these rules compliant with international benchmark. Resource use within the territorial sea is strictly reserved to the coastal State.

Territorial sea, as defined by the 1982 United Nations Convention on the Law of the ocean[2] , may be a belt of coastal waters extending at the most 12 nautical miles (22.2 km; 13.8 mi) from the baseline (usually the mean low-water mark) of a coastal state. The territorial sea is taken into account the sovereign territory of the state, although foreign ships (military and civilian) are allowed innocent passage through it, or transit passage for straits; this sovereignty also extends to the airspace over and seabed below. Adjustment of those boundaries is named, in law of nations, maritime delimitation.

A state’s territorial sea extends up to 12 nautical miles (22.2 km; 13.8 mi) from its baseline. If this is often ready to overlap with another state’s territorial sea, the border is taken because the median point between the states’ baselines, unless the states in question agree otherwise. A state also can prefer to claim a smaller territorial sea.

Problem of Breadth of Territorial Waters

The breadth of the territorial sea has remained a tricky issue, and up to 18th century the opinion was that breadth of territorial sea extends to the range of a ‘cannon-shot’ which at that time was three nautical miles. The three-mile rule which is popularly known as ‘cannon-shot’ rule was promulgated by the Dutch jurist, Bynkershock. He had a hypothesis that a State’s sovereignty broaden to the sea as far as a canon or fire could reach.

In order to fix breadth of the maritime belt, first important attempt was made by the league of the Nations. The Hague Conference of 1930 made an unsuccessful attempt to obtain consensus of the nations on a specific breadth of territorial sea. Since, International Law could not fix definite breadth of maritime belt, different countries claimed different breadths. In order to resolve this problem, Geneva Conference on the Law of the sea was called but the controversy could not be resolved. For the same purpose another conference, known as UN Convention on the Law of the Sea was called in 1960. In this conference, America presented a compromise formula which provided that the breadth of territorial waters should be 6 miles and beyond these 6 miles rights for fishing etc. for another 6 miles. The proposal was defeated by majority of a single vote.

Before the 1982, Sea Convention was concluded; States announced varying breadth of the territorial sea, ranging from 3 to 12 miles, though in certain cases they had state publicly wider areas comparatively, in few cases up to 200 nautical miles. But at the UNCLOS-III, claims broader than 12 miles did not find favour and the 12 miles rule was accepted by the Conference, which may be considered the present customary international law position.

The U.N. Convention of 1982 under Article 3 adopts the twelve-mile limit as a breadth of the territorial sea.  It provides that every State has the right to establish the breadth of its territorial sea up to a limit not exceeding 12 nautical miles measured from baselines determined in accordance with the Convention. Two methods have been laid down for measuring the breadth of the territorial sea:

  1. The low-water line 2. The straight baseline.

 The normal method used is the low-water line as marked on large-scale charts officially recognized by coastal State.

The method of straight baseline was expressed by the Anglo Norwegian Fisheries case, which had a decisive effect on the baseline issue.

Innocent Passage

Under the 1982, the sovereignty of a coastal State over its territorial water has a vital limitation that is the right of innocent passage enjoyed by ships (merchant ships, governmental ships and warships) of all States, whether coastal or landlocked, over the territorial sea of the coastal State.  Passage means navigation through the territorial sea for the purpose of passing through that sea with no entering into internal waters or calling at a roadstead or port facility outside internal waters. Passage must be continuous and efficient; however, it may include stopping and anchoring in so far as they are incidental to ordinary navigation or are rendered necessary by inevitable accident or anguish or for the purpose of rendering assistance to persons, ships or aircraft in danger or trouble.  Passage must take place in conformity with the 1982 Convention and with other rules of International Law.

 Passage must be innocent; it is innocent so long as it is not detrimental to the peace, order or security of the coastal State. The coastal States has the right to make laws to regulate the territorial waters. It can implement laws and regulations governing innocent passage, and to prevent passage which is not innocent. Foreign ships in the innocent passage are required to comply with all such laws and regulations, framed by the coastal State, and other common international regulations for the prevention of collisions at sea.

The 1982 Conventions provides that the coastal State must not hamper the innocent passage of foreign ships through its territorial seas except in accordance with the Convention. The Coastal State, within the application of the Convention or of any laws or regulations adopted in conformity with it, must not impose requirements aiming at denying or impairing the right of innocent passage, or discriminate on form or actually against the ships of any State or against ships carrying cargoes to, from or on behalf of any State. It must give appropriate publicity to any danger to navigation, of which it’s knowledge, within its territorial sea. It must not levy any charges upon foreign ships by reason only of their passage through its territorial sea; charges could also be levied as payment just for specific services rendered to the ship.[3]

The coastal State is under an obligation not to exercise its criminal jurisdiction on foreign ship elapsing through its territorial sea, except in the cases precise by the Convention. It is also under an obligation not to exercise civil jurisdiction in relation to a foreign ship or a person on its board, except in the cases specified by the Convention. Remarkably, the warships and other government ships operated for non-commercial purposes are exempted from any jurisdiction; however the coastal State, during a case of failure of any of those ships from obeying with its laws and regulations, may order it to leave its territorial Sea immediately.

The right of innocent passage is additionally enjoyed by submarines and other underwater vehicles. However, it is required that they pilot on the surface and show their flag.

Rights of the Coastal State over the Territorial Sea[4]                

As the 1982 Convention provides, the sovereignty of the coastal State extends to its territorial sea as well as to the air-space over its territorial sea, its bed and subsoil.  In this regard the coastal State enjoys the following:

(1)     The exclusive right to fish, and to exploit the resources of the seabed and subsoil of its territorial sea.

(2)     The exclusive right in the air-space over its territorial sea to the exclusion of other States. Foreign aircrafts, unlike ships, have no right of innocent fly in the air-space over the territorial sea of a State.

(3)     The right to enact laws and regulations, in conformity with the 1982 Convention and other rules of International Law, particularly in respect of navigation, health, customs, immigration and preservation of the environment.

(4)     The right to take the necessary steps in its territorial Sea to prevent passage which is not innocent.

(5)     The exercise of criminal jurisdiction on board of a foreign ship (arresting any person or conducting any investigation in connection with any crime committed on board of the foreign ship) in the following cases: if the consequences of the crime extend to it; if the crime is of a kind to disturb the peace of the country or the good order of its territorial sea; if the assistance of the local authorities has been requested; if the measures are necessary for the suppression of illicit traffic in narcotic drugs; or after leaving its internal water.

(6)     The exercise of civil jurisdiction in relation to a foreign ship (levy execution against or arrest the ship for the purpose of any civil proceedings) in respect of obligations or liabilities assumed or incurred by the ship itself in the course or for the purpose of its voyage through its waters, or in respect of any civil proceedings against a foreign ship after leaving its internal waters.

[1] Art. 2 UN Convention on the Law of the Sea; Arts 1–2, Geneva Convention on the Territorial Sea and the Contiguous Zone



[4] The 1982 Convention on the Law of the Sea, Article 2, 21, 22, 25-28.