Upgrad LLM

Territorial Sea

Development of Law of Sea

The law of the sea, which exists in the codified form today was totally different in the past and was much concerned and associated with the customary rules and was observed by the States as customary rules of international law.

At the very inception of the 17th century, Grotius propounded the principle of "Mare Liberum" which means freedom of the seas. According to this principle, sea is made for all and accessible to all and there is no regulation for any country in regards to its activities in the oceans or the seas. It was often termed as open seas.

By the mid 20th century, trade and commerce developed rapidly and it was realized that sea is one of the most important resources and need of demarcation of sea was felt to exploit the inexhaustible use of sea. As a result, the concept of open seas and freedom of seas eclipsed by many states making their claims over the seas to protect their interests, especially in regard to economic and military interests.

All this further stressed codification of law relating to seas in order to achieve uniformity and resolve maritime conflicts among nations. It was thus put as an agenda of International Law Commission in 1949 and later First United Nations Conference on Law of Sea (UNCLOS) took place at Geneva in 1958.

The conference resulted in adoption of four Conventions:

1. Convention on the Territorial Sea and Contiguous Zone.
2. Convention on High Seas.
3. Convention on Fishing and Conservation of Living Resources.
4. Convention on the Continental Shelf.

Subsequent to the adoption of the 1958 Conventions on the Law of the Sea, at the first United Nations Conference on the Law of the Sea, the General Assembly requested the Secretary-General to convene a Second United Nations Conference on the Law of the Sea to consider the topics of the breadth of the territorial sea and fishery limits, which had not been agreed upon in the said Conventions. Hence the Second United Nations Conference on the Law of the Sea took place in Geneva in 1960 but failed to resolve the above issues.

Finally, the General Assembly of UN resolved to convene the Third United Nations Conference on Law of the Seas. During 1973-1982 twelve sessions took place and in 1982 The Convention on Law of Seas, 1982 was finalized.


The Conference of 1958 defined the Territorial Sea but left the issue of breadth of territorial sea undecided. The Second Conference at Geneva in 1960 also failed to resolve the issues. It was after the Third Conference on Law of Sea [UNCLOS III], United Nations Convention on the Law of Sea, 1982 defined territorial sea as well as determined the breadth of Territorial Sea.

Part II of the 1982 Convention deals with the Territorial Sea. Article 2 under the head General Provisions deals with ‘Legal status of the territorial sea, of the air space over the territorial sea and of its bed and subsoil’.


Article 2(1) of United Nations Convention on the Law of Sea, 1982 states, the sovereignty of a coastal State extends, beyond its land territory and internal waters and, in the case of an archipelagic State, its archipelagic waters, to an adjacent belt of sea, described as the territorial sea. Article 2(2) states this sovereignty extends to the air space over the territorial sea as well as to its bed and subsoil. Article 2(3) states the sovereignty over the territorial sea is exercised subject to this Convention and to other rules of international law.

Hence, Territorial Sea is the belt of sea which is adjacent to the coastal state and upon which the coastal state exercises the sovereignty. This right over territory is compulsory and there is no discretion upon the state whether to exercise this right or not.

The two important aspects involved in concept of territorial sea are Breadth of the Territorial Sea and The Rights of States over the Territorial Sea.


Historical Background

Initially, there was incongruity between the states as to what the limit is or how far the territorial sea may be extended from the baselines. It is important and necessary to determine limit of the breadth of territorial sea as the coastal States exercises sovereignty over that part of the sea.

As the main motive of coastal state to claim the belt of sea was for its protection many propounders like Grotius suggested that sovereignty of the coastal state over the maritime belt should extend only to that area which could be commanded and controlled by artillery on the shore. As a result ‘canon shot’ rule was adopted but with the advancement of science and technology the range of Canon increased and varied. This lets to adoption of three nautical mile rule by the big maritime powers such as The United States and Great Britain which was followed by many other countries. With the passage of time and after the First World War, need to increase the breadth of territorial sea was felt and efforts were made to extend breadth of territorial sea.

The 1958 Geneva Convention on the Territorial Sea did not include an Article on the subject because of disagreements between the states, while the 1960 Geneva conference failed to accept the United States and Canadian proposal for a six-mile territorial sea.

Breadth Determined    

Article 3 under Section 2 of the Convention deals with Breadth of the Territorial Sea. It states 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 this Convention.


Article 5 under Section 2 of the Convention deals with Normal baseline. It sates, except where otherwise provided in this Convention, the normal baseline for measuring the breadth of the territorial sea is the low-water line along the coast as marked on large-scale charts officially recognised by the coastal State. It is well settled that in the normal coast the low-water line is the normal baseline.

By virtue of the 1982 Convention on Law of Seas, the low-water line of a low-tide elevation may be used as a baseline for measuring the breadth of territorial sea if it is situated wholly or partly at a distance not exceeding the breadth of the territorial sea from the mainland or the island and that part of water between mainland and low tide elevation will be called Archipelagic waters.  If it is beyond this distance, it will have no territorial sea of its own and the whole area is treated as archipelagic waters and beyond that lays Contiguous Zone.

Sometimes, the geography of the state coast is in such a way as to cause problems to measure territorial sea from the coastline; for instance, where the coastline is deeply indented or there are numerous islands running parallel to the coasts, or where there exits bays cutting into coastlines, hence special rules have evolved to deal with this issue.

Anglo-Norwegian Fisheries Case ICJ Reports 1951 P 116 is a leading case in this regard. The case concerned Norwegian decree delimiting its territorial sea along some 1000 miles of its coastline. However, instead of measuring the territorial sea from the low-water line which should be the normal baseline as per settled rule, the Norwegian constructed a sequence of straight baselines linking the outermost part of the land running along the border of islands which parallels the Norwegian coastline. This had the effect of enclosing within its territorial limits parts of what would normally have been high seas if the traditional method had been used. As a result, dispute between British fishing boats arose and the UK challenged the legality of the straight baseline system under international law.

The court held that it was the straight outline drawn along the most seaward par on the islands was relevant in establishing the baselines, and not the low-water line of the mainland. This was dictated by geographic, historic and economic certainty. The normal method of drawing baselines that are parallel to the coast was not applicable in this case because it would necessitate complex geometrical constructions which will further cause confusion, as a result the concept of straight baselines drawn from the outer rocks can be considered. The Norwegians had applied this system over the years without any objections from anyone and it was only after these many years the UK intervened.

Thus, although Norwegian rights had been established through actual practice coupled with compliance, the court regarded the straight baseline system itself as a valid principle of international law in view of special geographic conditions of the area. The court provided criteria for determining the acceptability of any such delimitation. The drawing of the baseline had not to depart from the general direction of the coast, in view of the close dependence of the territorial sea upon the land domain; the baselines had to be drawn so that the sea area lying within them had to be sufficiently closely linked to the land domain to be subject to the regime of internal waters, and it was permissible to consider in the process certain economic interests peculiar to a region, the reality and importance of which are evidence by long usage. What matters for the determination of the legality of straight baseline system is the cumulative effect of geographic, historic and economic interests.

Delimitation of the territorial sea between States with opposite or adjacent coasts

Apart from geographical conditions; a situation may arise when states have opposite or adjacent coasts and straight baseline method may cause conflicts e.g. India has opposite coasts with Srilanka and adjacent coasts with Pakistan. Article 15 under Section 2 of United Nations Convention on Law of the Sea, 1982 provides for delimitation of the territorial sea between States with opposite or adjacent coasts. It provides where the coasts of two States are opposite or adjacent to each other, neither of the two States is entitled, failing agreement between them to the contrary, to extend its territorial sea beyond the median line every point of which is equidistant from the nearest points on the baselines from which the breadth of the territorial seas of each of the two States is measured. This provision does not apply, however, where it is necessary by reason of historic title or other special circumstances to delimit the territorial seas of the two States in a way which is at variance therewith.

In Maritime Delimitation and Territorial Question (Qatar V. Bahrain) I.C.J., 1994 I.C.J. 112 The case concerned with Qatar proceedings against Bahrain in respect of certain disputes between the two states relating to sovereignty over some territories and the delimitation of the maritime areas of the two states. Qatar requested the Court to adjudge and declare, in accordance with international law that one, Qatar has sovereignty over disputed territories and second, to draw a single maritime boundary between the maritime areas of seabed, subsoil and superjacent waters appertaining respectively to the state of Qatar and Bahrain.

Coming to the question of delimitation of maritime the court observed that the boundary, the court expected to draw, therefore, would delimit exclusively their territorial seas and consequently an area over which they enjoy territorial sovereignty. The concept of single maritime boundary does not stem from multilateral treaty but from state practice. The parties agreed that the provisions of article 15 of 1982 Convention on the law of sea are part of customary law. It was referred to as equidistant rule. The court went on to declare that, the most logical and widely practised approach is first to draw provisionally an equidistance line and then to consider whether that line must be adjusted in the light of the existence of special circumstances. The court also stated that the equidistance line is the line every point of which is equidistance from the nearest points on the baselines from which the breadth of the territorial sea of each of the two states is measured.

The court reached to the conclusion that it is in a position to determine the course of that part of the single maritime boundary, which will delimit the territorial seas of the parties. Then the court decided that from the point of intersection of the respective maritime limits of Saudi Arab on the one hand and Qatar on the other, the boundary will follow a north-easterly direction, then immediately turn in easterly direction, after which it will pass between Jarirat Hawar and Janan; it will subsequently turn to north and pass between Qitat Jaradah on Bahrain side and Fasht Oibal on Qatar side.

The court thus held that the single maritime boundary that divides the various maritime zones of the state of Qatar and state of Bahrain shall be drawn.


Sovereignty over Territorial Sea

The sovereignty over territorial sea automatically belongs to territorial state e.g. a newly independent state which has a coast come into existence is entitled to the territorial sea. It cannot be disputed that the coastal state enjoys sovereign rights over its maritime belt and extensive jurisdictional control, having regard to the relevant rules of international law. The fundamental restriction upon sovereignty of the coastal state is the right of other nations to innocent passage through the territorial sea, and this distinguishes the territorial sea from the internal waters of the state, which are fully within the unrestricted jurisdiction of the coastal nation.

Article 2 under Section 1 of United Nations Convention on Law of Sea, 1982 provide that the coastal state’s sovereignty extends over its territorial sea and to the airspace and seabed and subsoil thereof, subject to the provisions of this Convention and of International law. The territorial sea thus forms an indisputable part of the land territory to which it is bound.

It depends from state to state that how far it chooses to exercise the jurisdiction and sovereignty to which it may lay claim under the principles of international law will depend upon the terms of its own municipal legislation, and some states will not wish to take advantage of the full extent of the powers permitted to them given the international legal system.

Hence, the coastal state by virtue of its sovereignty has the power, if it so desires, not to permit or restrain any foreign national or any foreign vessels from entering its territorial sea subject to any agreements or innocent passage, and reserve certain activities like fishing or mining for its own citizens. The coastal state also has extensive powers of control relating to, amongst others, security and custom matters.

Coastal States Jurisdiction over Foreign Ships

The coastal state may only exercise its criminal jurisdiction with regard to the arrest of any person or the investigation of any matter connected with a crime committed on a foreign ship in defined situations. These situations are given under Article 27 of The United Nations Convention on Law of Seas, 1982 as (a) if the consequences of the crime extend to the coastal State; (b) if the crime is of a kind to disturb the peace of the country or the good order of the territorial sea; (c) if the assistance of the local authorities has been requested by the master of the ship or by a diplomatic agent or consular officer of the flag State; or (d) if such measures are necessary for the suppression of illicit traffic in narcotic drugs or psychotropic substances.

Under Article 28 of the 1982 Convention, the coastal state should not stop or divert a foreign ship passing through its territorial sea for the purpose of exercising civil jurisdiction in relation to a person on board ship, nor levy execution against or arrest a ship , unless obligations are involved which was assumed by the ship itself in the course of, or for the purpose of, its voyage through waters of the coastal state, or unless the ship is passing through the territorial sea on its way from internal waters. The above rules do not, however, prejudice the right of the state to levy execution against or to arrest, for the purpose of any civil proceedings, of foreign ship lying in the territorial sea or passing through the territorial sea after leaving internal waters.

Article 29 to Article 32 of the 1982 Convention provides that warships and other governmental ships operated for non-commercial purposes are immune from the jurisdiction of the coastal state, although they may be required to leave the territorial sea immediately for breach of rules governing passage and the flag state will bear international responsibility in cases of loss or damage suffered as a result.

The Right of Innocent Passage

The right of foreign merchant ship other than warships to pass unhindered through the territorial sea of a coastal state has been accepted as a customary international law principle. However it is necessary that the passage has to be innocent. Innocent passage may be defined as such which is not detrimental to coastal state or the world community as whole. If the passage is likely to cause any harm to security and well being which might be costly, politically and economically to the coastal state, it reserves the right to ward away such a danger.

Article 19(1) of the United Nations Convention on law of the Sea, 1982 provides that Passage is innocent so long as it is not prejudicial to the peace, good order or security of the coastal State. Such passage shall take place in conformity with this Convention and with other rules of international law.

Article 19(2) of the United Nations Convention on law of the Sea, 1982 provides that passage of a foreign ship shall be considered to be prejudicial to the peace, good order or security of the coastal State if in the territorial sea it engages in any of the following activities: (a) any threat or use of force against the sovereignty, territorial integrity or political independence of the coastal State, or in any other manner in violation of the principles of international law embodied in the Charter of the United Nations; (b) any exercise or practice with weapons of any kind; (c) any act aimed at collecting information to the prejudice of the defence or security of the coastal State; (d) any act of propaganda aimed at affecting the defence or security of the coastal State; (e) the launching, landing or taking on board of any aircraft; (f) the launching, landing or taking on board of any military device; (g) the loading or unloading of any commodity, currency or person contrary to the customs, fiscal, immigration or sanitary laws and regulations of the coastal State; (h) any act of wilful and serious pollution contrary to this Convention; (i) any fishing activities; (j) the carrying out of research or survey activities; (k) any act aimed at interfering with any systems of communication or any other facilities or installations of the coastal State; (l) any other activity not having a direct bearing on passage. Thus the state may take necessary steps to ward away any of such dangers or threats which are likely to fall upon them.

However, by virtue of Article 24 of the 1982 Convention, coastal states must not hamper the innocent passage of foreign ships, either by imposing requirements upon them which would have the practical effect of denying or impairing the right or by discrimination. It also provides that the coastal State shall give appropriate publicity to any danger to navigation, of which it has knowledge, within its territorial sea.

It has been established that foreign ships exercising the right of innocent passage are to comply with laws and regulations enacted by the coastal state, in particular, those relating to transport and navigation. This was developed in Article 21(1) of the 1982 Convention which expressly provided that the coastal State could adopt laws and regulations concerning passage with regard to:

(a) the safety of navigation and the regulation of maritime traffic;

(b) the protection of navigational aids and facilities and other facilities or installations;

(c) the protection of cables and pipelines;

(d) the conservation of the living resources of the sea;

(e) the prevention of infringement of the fisheries laws and regulations of the coastal State;

(f) the preservation of the environment of the coastal State and the prevention, reduction and control of pollution thereof;

(g) marine scientific research and hydro graphic surveys;

(h) the prevention of infringement of the customs, fiscal, immigration or sanitary laws and regulations of the coastal State.

Article 21(3) further provides that the coastal State shall give due publicity to all such laws and regulations and 21(4) imposes a duty on foreign ships by providing that Foreign ships exercising the right of innocent passage through the territorial sea shall comply with all such laws and regulations and all generally accepted international regulations relating to the prevention of collisions at sea.


Law on Territorial Sea has evolved over a period of time and developed through various International Conferences and Convention. Territorial Sea forms an indispensible part of the coastal state and has tremendous strategic, economic and navigational importance. The United Nations Convention on Law of Seas, 1982 is of great importance in regards to law on territorial waters or seas and determines the rights and duties of various states towards each other in relations to the territorial waters and also determines the extent of territorial waters of the coastal states.

In India Article 297 of the Constitution of India and The Maritime Zones Act, 1976 deals with laws relating to territorial waters and vests The Union of India the sovereignty over the territorial sea. The Act provides that the limit of territorial waters is the line every point of which is at a distance of 12 nautical miles from the nearest point of appropriate baseline. It also provides that all foreign ships other than warships shall enjoy the right of innocent passage through the territorial waters. Passage shall be innocent as long as it is not prejudicial to the peace, good order or security of India and if it is not so the state has the power to suspend such passage. Therefore India’s position is consistent to that of the Convention on Law of the Sea, 1982. 


-Sahil Khurana, 3rd Year, Vivekananda Institute of Professional Studies, GGSIPU


Tags :
Published in Others
Views : 611
Other Articles by - Navin Kumar Jaggi
Report Abuse



CrPC MASTERCLASS!     |    x