Montreux Convention and Canal Istanbul

Debates continue unabated in the Turkish media on the question of digging a canal to be called "Canal Istanbul", to link the Marmara Sea to the Black Sea. This is what Turkish President Recep Tayyip Erdoğan described as his “crazy project”.

The public interest is focused on its cost, its potential damage on the environment and the public funds that would be channelled to construction companies close to the government. There is also widespread gossip about the profiteering by people who, thanks to insider information, have purchased land along the eventual route of the canal.

This article will focus on the international law concerning the project. The international convention signed in Montreux, Switzerland in 1936 regulates passage through the Turkish Straits – the Dardanelles, Bosporus and Marmara Sea. The convention recognises the international status of the straits, but also gives Turkey a central role in overseeing its proper implementation. 

The Montreux Convention aspect of the canal project has been debated in Turkish media only superficially. It is more thoroughly debated in the social media networks of international law professionals and retired Turkish diplomats. 

Erdoğan believes the canal would be “totally outside scope of application of the Montreux Convention”. He challenged the “right of 200,000-ton oil tankers to use the Bosporus under the freedom of passage. Some may not dare say this,” he said. “But I can. If there is a threat to our European and Asian shores, then we would do whatever is necessary to prevent it”. 

Turkey is of course entitled to take any measure within its jurisdiction, but cannot change the fact that the Bosporus is an international sea lane and its status is regulated by an international convention.

Before the Montreux Convention, passage through the Turkish Straits was regulated by another convention annexed to the Peace Treaty signed in Lausanne in 1923. That convention imposed several restrictions to setting up military installations within a certain distance of the straits and the Marmara Sea. 
Turkey, using a favourable constellation in the mid-1930s, persuaded the states that were party to the convention attached to the Lausanne Peace Treaty to replace it with a new one. This was possible because of the insecurity that prevailed in Europe at the time: Italy had invaded Abyssinia and the League of Nations was not able to prevent it. Germany was threatening to invade Czechoslovakia. 

Turkey used this precarious atmosphere to persuade the parties to the convention to adjust it to the new conditions and was able to re-militarise the shores of the straits and the Marmara Sea. As a result, the new Montreux Convention was signed that took better care of Turkey’s and Russia’s security concerns. It also protected the interests of the other Black Sea coastal countries. The Montreux Convention was signed for 20 years, a period that could be renewed by tacit consent. 

The unlimited freedom of passage for the merchant ships is maintained for all countries in by the Montreux Convention. Turkey’s security is improved by limiting the passage if it is at war. 

Russia’s security was taken care of by limiting the tonnage of military vessels of non-Black Sea countries allowed to enter the Black Sea. The aggregate tonnage of their military vessels is limited to 30,000 tons and the period of their stay in the Black Sea cannot exceed 21 days. 

The United States is not party to the Montreux Convention therefore it has no right to propose amendment or terminate it, but it is willing to keep a naval presence in the Black Sea. During the 2008 South Ossetia crisis between Russia and Georgia, the United States wanted to send a 68,000-ton hospital ship to Georgian shores, but Turkey informed Washington that this would be an infraction of the Montreux Convention and the U.S. Navy instead sent a 12,000 ton-ship. 

What would be Turkey’s response if the United States decided to send military vessels to the Black Sea above the limits set by the Montreux Convention and asks for Ankara to agree to send them through the ‘Canal Istanbul’, claiming that Montreux limitations are valid only for the Bosporus? Montreux’s relevance to the Canal Istanbul would then be sorely tested.

The opinions expressed in this column are those of the author and do not necessarily reflect those of Ahval.