Forum of adoption: Diplomatic Conference
In force: no
Entry into force: 14.09.1937
During the Spanish Civil War, nine Powers agreed to take collective measures to suppress attacks by submarines against merchant vessels. The Agreement refers in the preamble to the provisions of the London Treaty of 1930 and the procès-verbal of 1936 concerning submarine warfare. In the Supplementary Agreement of 17 September 1937 the same Powers made the principles of the first Agreement applicable to attacks by surface vessels and aircraft.
Meetings of forum; 09.09.1937 – 14.09.1937, Nyon
Date of adoption: 14.09.1937
Number of articles: 9
Authentic textEnglish; French
Source D.Schindler and J.Toman, The Laws of Armed Conflicts, Martinus Nihjoff Publisher, 1988, pp.887-889.
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Whereas arising out of the Spanish conflict attacks have been repeatedly committed in the Mediterranean by submarines against merchant ships not belonging to either of the conflicting Spanish parties; and
Whereas these attacks are violations of the rules of international law referred to in Part IV of the Treaty of London of 22 April 1930, with regard to the sinking of merchant ships and constitute acts contrary to the most elementary dictates of humanity, which should be justly treated as acts of piracy; and
Whereas without in any wily admitting the right of either party to the conflict in Spain to exercise belligerent rights or to interfere with merchant ships on the high seas even if the laws of warfare at sea are observed and without prejudice to the right of any participating Power to take such action as may be proper to protect its merchant shipping from any kind of interference on the high seas or to the possibility of further collective measures being agreed upon subsequently, it is necessary in the first place to agree upon certain special collective measures against piratical acts by submarines: