Convention relating to the Straits
THE BRITISH EMPIRE, FRANCE, ITALY, JAPAN, BULGARIA, GREECE, ROUMANIA, RUSSIA, the SERB-CROAT-SLOVENE STATE and TURKEY, being desirous of ensuring in the Straits freedom of transit and navigation between the Mediterranean Sea and the Black Sea for all nations, in accordance with the principle laid down in Article 23 of the Treaty of Peace signed this day,
And considering that the maintenance of that freedom is necessary to the general peace and the commerce of the world,
Have decided to conclude a Convention to this effect, and have appointed as their respective Plenipotentiaries:
HIS MAJESTY THE KING OF THE UNITED KINGDOM OF GREAT BRITAIN AND IRELAND AND OF THE BRITISH DOMINIONS BEYOND THE SEAS, EMPEROR OF INDIA: The Right Honourable Sir Horace George Montagu Rumbold, Baronet, G.C.M.G., High Commissioner at Constantinople;
THE PRESIDENT OF THE FRENCH REPUBLIC: General Maurice Pellé, Ambassador of France, High Commissioner of the Republic in the East, Grand Officer of the National Order of the Legion of Honour;
HIS MAJESTY THE KING OF ITALY: The Honourable Marquis Camillo Garroni, Senator of the Kingdom, Ambassador of Italy, High Commissioner at Constantinople, Grand Cross of the Orders of Saints Maurice and Lazarus, and of the Crown of Italy; M. Giulio Cesare Montagna, Envoy Extraordinary and Minister Plenipotentiary at Athens, Commander of the Order of Saints Maurice and Lazarus, Grand Officer of the Crown of Italy;
HIS MAJESTY THE EMPEROR OF JAPAN: Mr. Kentaro Otchiai, Jusammi, First Class of the Order of the Rising Sun, Ambassador Extraordinary and Plenipotentiary at Rome;
HIS MAJESTY THE KING OF THE BULGARIANS: M. Bogdan Morphoff, formerly Minister of Railways, Posts and Telegraphs; M. Dimitri Stancioff, Doctor of Law, Envoy Extraordinary and Minister Plenipotentiary at London, Grand Cross of the Order of Saint Alexander;
HIS MAJESTY THE KING OF THE HELLENES: M. Eleftherios K. Veniselos, formerly President of the Council of Ministers, Grand Cross of the Order of the Saviour; M. Demetrios Caclamanos, Minister Plenipotentiary at London, Commander of the Order of the Saviour;
HlS MAJESTY THE KING OF ROUMANIA: M. Constantine I. Diamandy, Minister Plenipotentiary; M. Constantine Contzesco, Minister Plenipotentiary;
RUSSIA: M. Nicolas Ivanovitch Iordanski;
HIS MAJESTY THE KING OF THE SERBS, THE CROATS AND THE SLOVENES: Dr. Miloutine Yovanovitch, Envoy Extraordinary and Minister Plenipotentiary at Berne;
THE GOVERNMENT OF THE GRAND NATIONAL ASSEMBLY OF TURKEY: Ismet Pasha, Minister for Foreign Affairs, Deputy for Adrianople; Dr. Riza Nour Bey, Minister for Health and for Public Assistance, Deputy for Sinope; Hassan Bey, formerly Minister, Deputy for Trebizond;
Who, having produced their full powers, found in good and due form, have agreed as follows:
ARTICLE 1. 
The High Contracting Parties agree to recognise and declare the principle of freedom of transit and of navigation by sea and by air in the Strait of the Dardanelles, the Sea of Marmora and the Bosphorus, hereinafter comprised under the general term of the "Straits."
ARTICLE 2. 
The transit and navigation of commercial vessels and aircraft, and of war vessels and aircraft in the Straits in time of peace and in time of war shall henceforth be regulated by the provisions of the attached Annex.
Rules for the Passage of Commercial Vessels and Aircraft, and of War Vessels and Aircraft through the Straits.
1. Merchant Vessels, including Hospital Ships, Yachts and Fishing Vessels and non-Military Aircraft.
(a) In Time of Peace.
Complete freedom of navigation and passage by day and by night under any flag and with any kind of cargo, without any formalities, or tax, or charge whatever (subject, however, to international sanitary provisions) unless for services directly rendered, such as pilotage, light, towage or other similar charges, and without prejudice to the rights exercised in this respect by the services and undertakings now operating under concessions granted by the Turkish Government.
To facilitate the collection of these dues, merchant vessels passing the Straits will communicate to stations appointed by the Turkish Government their name, nationality, tonnage and destination.
Pilotage remains optional.
(b) In Time of War, Turkey being Neutral.
Complete freedom of navigation and passage by day and by night under the same conditions as above. The duties and rights of Turkey as a neutral Power cannot authorise her to take any measures liable to interfere with navigation through the Straits, the waters of which, and the air above which, must remain entirely free in time of war, Turkey being neutral just as in time of peace.
Pilotage remains optional.
(c) In Time of War, Turkey being a Belligerent.
Freedom of navigation for neutral vessels and neutral non-military aircraft, if the vessel or aircraft in question does not assist the enemy, particularly by carrying contraband, troops or enemy nationals. Turkey will have the right to visit and search such vessels and aircraft, and for this purpose aircraft are to alight on the ground or on the sea in such areas as are specified and prepared for this purpose by Turkey. The rights of Turkey to apply to enemy vessels the measures allowed by international law are not affected.
Turkey will have full power to take such measures as she may consider necessary to prevent enemy vessels from using the Straits. These measures, however, are not to be of such a nature as to prevent the free passage of neutral vessels, and Turkey agrees to provide such vessels with either the necessary instruction or pilots for the above purpose.
2. Warships, induding Fleet Auxiliaries, Troopships, Aircraft Carriers and Military Aircraft.
(a) In Time of Peace.
Complete freedom of passage by day and by night under any flag, without any formalities, or tax, or charge whatever, but subject to the following restrictions as to the total force:
The maximum force which any one Power may send through the Straits into the Black Sea is not to be greater than that of the most powerful fleet of the littoral Powers of the Black Sea existing in that sea at the time of passage; but with the proviso that the Powers reserve to themselves the right to send into the Black Sea, at all times and under all circumstances, a force of not more than three ships, of which no individual ship shall exceed 10,000 tons.
Turkey has no responsibility in regard to the number of war vessels which pass through the Straits.
In order to enable the above rule to be observed, the Straits Commission provided for in Article 10 will, on the 1st January and the 1st July of each year, enquire of each Black Sea littoral Power the number of each of the following classes of vessel which such Power possesses in the Black Sea: Battle-ships, battle-cruisers, aircraft-carriers, cruisers, destroyers, submarines, or other types of vessels as well as naval aircraft; distinguishing between the ships which are in active commission and the ships with reduced complements, the ships in reserve and the ships undergoing repairs or alterations.
The Straits Commission will then inform the Powers concerned that the strongest naval force in the Black Sea comprises: Battleships, battle-cruisers, aircraft carriers, cruisers, destroyers, submarines, aircraft and units of other types which may exist. The Straits Commission will also immediately inform the Powers concerned when, owing to the passage into or out of the Black Sea of any ship of the strongest Black Sea force, any alteration in tha[sic] force has taken place.
The naval force that may be sent through the Straits into the Black Sea will be calculated on the number and type of the ships of war in active commission only.
(b) In Time of War, Turkey being Neutral.
Complete freedom of passage by day and by night under any flag, without any formalities, or tax, or charge whatever, under the same limitations as in paragraph 2 (a),
However, these limitations will not be applicable to any belligerent Power to the prejudice of its belligerent rights in the Black Sea.
The rights and duties of Turkey as a neutral Power cannot authorise her to take any measures liable to interfere with navigation through the Straits, the waters of which, and the air above which, must remain entirely free in time of war, Turkey being neutral, just as in time of peace.
Warships and military aircraft of belligerents will be forbidden to make any capture, to exercise the right of visit and search, or to carry out any other hostile act in the Straits
As regards revictualling and carrying out repairs, war vessels will be subject to the terms of the Thirteenth Hague Convention of 1907, dealing with maritime neutrality.
Military aircraft will receive in the Straits similar treatment to that accorded under the Thirteenth Hague Convention of 1907 to warships, pending the conclusion of an international Convention establishing the rules of neutrality for aircraft.
(c) In Time of War, Turkey being Belligerent.
Complete freedom of passage for neutral warships, without any formalities, or tax, or charge whatever, but under the same limitations as in paragraph 2 (a).
The measures taken by Turkey to prevent enemy ships and aircraft from using the Straits are not to be of such a nature as to prevent the free passage of neutral ships and aircraft, and Turkey agrees to provide the said ships and aircraft with either the necessary instructions or pilots for the above purpose.
Neutral military aircraft will make the passage of the Straits at their own risk and peril, and will submit to investigation as to their character. For this purpose aircraft are to alight on the ground or on the sea in such areas as are specified and prepared for this purpose by Turkey.
3. (a) The passage of the Straits by submarines of Powers at peace with Turkey must be made on the surface.
(b) The officer in command of a foreign naval force, whether coming from the Mediterranean or the Black Sea, will communicate, without being compelled to stop, to a signal station at the entrance to the Dardanelles or the Bosphorus, the number and the names of vessels under his orders which are entering the Straits.
These signal stations shall be notified from time to time by Turkey; until such signal stations are notified, the freedom of passage for foreign war vessels in the Straits shall not thereby be prejudiced, nor shall their entry into the Straits be for this reason delayed.
(c) The right of military and non-military aircraft to fly over the Straits, under the conditions laid down in the present rules, necessitates for aircraft:
(i) Freedom to fly over a strip of territory of five kilometres on each side of the narrow parts of the Straits;
(ii) Liberty, in the event of a forced landing, to alight on the coast or on the sea in the territorial waters of Turkey.
4. Limitation of Time of Transit for Warships. In no event shall warships in transit through the Straits, except in the event of damage or peril of the sea, remain therein beyond the time which is necessary for them to effect their passage, including the time of anchorage during the night if necessary for safety of navigation.
5. Stay in the Ports of the Straits and of the Black Sea.
(a) Paragraphs 1, 2 and 3 of this Annex apply to the passage of vessels, warships and aircraft through and over the Straits and do not affect the right of Turkey to make such regulations as she may consider necessary regarding the number of men-of-war and military aircraft of any one Power which may visit Turkish ports or aerodromes at one time, and the duration of their stay.
(b) Littoral Powers of the Black Sea will also have a similar right as regards their ports and aerodromes.
(c) The light-vessels which the Powers at present represented on the European Commission of the Danube maintain as stationnaires at the mouths of that river as far up as Galatz will be regarded as additional to the men-of-war referred to in paragraph 2, and may be replaced in case of need.
6. Special Provisions relating to Sanitary Protection.
Warships which have on board cases of plague, cholera or typhus, or which have had such cases on board during the last seven days, and warships which have left an infected port within less than five times 24 hours must pass through the Straits in quarantine and apply by the means on board such prophylactic measures as are necessary to prevent any possibility of the Straits being infected.
The same rule shall apply to merchant ships having a doctor on board and passing straight through the Straits without calling at a port or breaking bulk.
Merchant ships not having a doctor on board shall be obliged to comply with the international sanitary regulations before entering the Straits, even if they are not to call at a port therein.
Warships and merchant vessels calling at one of the ports in the Straits shall be subject in that port to the international sanitary regulations applicable in the port in question.
ARTICLE 3. 
With a view to maintaining the Straits free from any obstacle to free passage and navigation, the provisions contained in Articles 4 to 9 will be applied to the waters and shores thereof as well as to the islands situated therein, or in the vicinity.
ARTICLE 4. 
The zones and islands indicated below shall be demilitarised:
(1) Both shores of the Straits of the Dardanelles and the Bosphorus over the extent of the zones delimited below:
On the north-west, the Gallipoli Peninsula and the area south-east of a line traced from a point on the Gulf of Xeros 4 kilometres north-east of Bakla-Burnu, reaching the Sea of Marmora at Kumbaghi and passing south of Kavak (this village excluded);
On the south-east, the area included between the coast and a line 20 kilometres from the coast, starting from Cape Eski-Stamboul opposite Tenedos and reaching the Sea of Marmora at a point on the coast immediately north of Karabigha.
Bosphorus (without prejudice to the special provisions relating to Constantinople contained in Article 8):
On the east, the area extending up to a line 15 kilometres from the eastern shore of the Bosphorus;
On the west, the area up to a line 15 kilometres from the western shore of the Bosphorus.
(2) All the islands in the Sea of Marmora, with the exception of the island of Emir Ali Adasi.
(3) In the Ægean Sea, the islands of Samothrace, Lemnos, Imbros, Tenedos and Rabbit Islands.
ARTICLE 5. 
A Commission composed of four representatives appointed respectively by the Governments of France, Great Britain, Italy and Turkey shall meet within 15 days of the coming into force of the present Convention to determine on the spot the boundaries of the zone laid down in Article 4 (1).
The Governments represented on that Commission will pay the salaries of their respective representatives.
Any general expenses incurred by the Commission shall be borne in equal shares by the Powers represented thereon.
ARTICLE 6 
Subject to the provisions of Article 8 concerning Constantinople, there shall exist, in the demilitarised zones and islands, no fortifications, no permanent artillery organisation, no submarine engines of war other than submarine vessels, no military aerial organisation, and no naval base.
No armed forces shall be stationed in the demilitarised zones and islands except the police and gendarmerie forces necessary for the maintenance of order; the armament of such forces will be composed only of revolvers, swords, rifles and four Lewis guns per hundred men, and will exclude any artillery.
In the territorial waters of the demilitarised zones and islands, there shall exist no submarine engines of war other than submarine vessels.
Notwithstanding the preceding paragraphs Turkey will retain the right to transport her armed forces through the demilitarised zones and islands of Turkish territory, as well as through their territorial waters, where the Turkish fleet will have the right to anchor.
Moreover, in so far as the Straits are concerned, the Turkish Government shall have the right to observe by means of aeroplanes or balloons both the surface and the bottom of the sea. Turkish aeroplanes will always be able to fly over the waters of the Straits and the demilitarised zones of Turkish territory, and will have full freedom to alight therein, either on land or on sea.
In the demilitarised zones and islands and in their territorial waters, Turkey and Greece shall similarly be entitled to effect such movements of personnel as are rendered necessary for the instruction outside these zones and islands of the men recruited therein.
Turkey and Greece shall have the right to organise in the said zones and islands in their respective territories any system of observation and communication, both telegraphic, telephonic and visual. Greece shall be entitled to send her fleet into the territorial waters of the demilitarised Greek islands, but may not use these waters as a base of operations against Turkey nor for any military or naval concentration for this purpose.
ARTICLE 7. 
No submarine engines of war other than submarine vessels shall be installed in the waters of the Sea of Marmora.
The Turkish Government shall not install any permanent battery or torpedo tubes, capable of interfering with the passage of the Straits, in the coastal zone of the European shore of the Sea of Marmora or in the coastal zone on the Anatolian shore situated to the east of the demilitarised zone of the Bosphorus as far as Darije.
ARTICLE 8. 
At Constantinople, including for this purpose Stamboul, Pera, Galata, Scutari, as well as Princes' Islands, and in the immediate neighbourhood of Constantinople, there may be maintained for the requirements of the capital, a garrison with a maximum strength of 12,000 men. An arsenal and naval base may also be maintained at Constantinople.
ARTICLE 9. 
If, in case of war, Turkey, or Greece, in pursuance of their belligerent rights, should modify in any way the provisions of demilitarisation prescribed above, they will be bound to re-establish as soon as peace is concluded the regime laid down in the present Convention.
ARTICLE 10. 
There shall be constituted at Constantinople an International Commission composed in accordance with Article 12 and called the "Straits Commission."
ARTICLE 11. 
The Commission will exercise its functions over the waters of the Straits.
ARTICLE 12. 
The Commission shall be composed of a representative of Turkey, who shall be President, and representatives of France, Great Britain, Italy, Japan, Bulgaria, Greece, Roumania, Russia, and the Serb-Croat-Slovene State, in so far as these Powers are signatories of the present Convention, each of these Powers being entitled to representation as from its ratification of the said Convention.
The United States of America, in the event of their acceding to the present Convention, will also be entitled to have one representative on the Commission.
Under the same conditions any independent littoral States of the Black Sea which are not mentioned in the first paragraph of the present Article will possess the same right.
ARTICLE 13. 
The Governments represented on the Commission will pay the salaries of their representatives. Any incidental expenditure incurred by the Commission will be borne by the said Governments in the proportion laid down for the division of the expenses of the League of Nations.
ARTICLE 14. 
It will be the duty of the Commission to see that the provisions relating to the passage of warships and military aircraft are carried out; these provisions are laid down in paragraphs 2, 3 and 4 of the Annex to Article 2.
ARTICLE 15. 
The Straits Commission will carry out its functions under the auspices of the League of Nations, and will address to the League an annual report giving an account of its activities, and furnishing all information which may be useful in the interests of commerce and navigation; with this object in view the Commission will place itself in touch with the departments of the Turkish Government dealing with navigation through the Straits.
ARTICLE 16. 
It will be the duty of the Commission to prescribe such regulations as may be necessary for the accomplishment of its task.
ARTICLE 17. 
The terms of the present Convention will not infringe the right of Turkey to move her fleet freely in Turkish waters.
ARTICLE 18. 
The High Contracting Parties, desiring to secure that the demilitarisation of the Straits and of the contiguous zones shall not constitute an unjustifiable danger to the military security of Turkey, and that no act of war should imperil the freedom of the Straits or the safety of the demilitarised zones, agree as follows:
Should the freedom of navigation of the Straits or the security of the demilitarised zones be imperilled by a violation of the provisions relating to freedom of passage, or by a surprise attack or some act of war or threat of war, the High Contracting Parties, and in any case France, Great Britain, Italy, and Japan, acting in conjunction, will meet such violation, attack, or other act of war or threat of war, by all the means that the Council of the League of Nations may decide for this purpose.
So soon as the circumstance which may have necessitated the action provided for in the preceding paragraph shall have ended, the regime of the Straits as laid down by the terms of the present Convention shall again be strictly applied.
The present provision, which forms an integral part of those relating to the demilitarisation and to the freedom of the Straits, does not prejudice the rights and obligations of the High Contracting Parties under the Covenant of the League of Nations.
ARTICLE 19. 
The High Contracting Parties will use every possible endeavour to induce non-signatory Powers to accede to the present Convention.
This adherence will be notified through the diplomatic channel to the Government of the French Republic, and by that.Government to all signatory or adhering States. The adherence will take effect as from the date of notification to the French Government.
ARTICLE 20. 
The present Convention shall be ratified. The ratification shall be deposited at Paris as soon as possible.
The Convention will come into force in the same way as the Treaty of Peace signed this day. In so far as concerns those Powers who are not signatories of this Treaty and who at that date shall not yet have ratified the present Convention, this Convention will come into force as from the date on which they deposit their respective ratifications, which deposit shall be notified to the other Contracting Powers by the French Government.
In faith whereof the above-named Plenipotentiaries have signed the present Convention.
Done at Lausanne the 24th July, 1923, in a single copy which will remain deposited in the archives of the Government of the French Republic, and of which authenticated copies will be transmitted to each of the Contracting Powers.
(L.S.)G. C. MONTAGNA.
(L.S.)E. K. VENISÉLOS.
(...... ) ........................................
(L.S.)DR. RIZA NOUR.