CIL Director Dr Nilufer Oral and Ocean Law and Policy Co-Head Dr Zhen Sun participated as members of the Group of Experts in the San Remo Manual on International Law Applicable to Armed Conflicts at Sea Update Project Meeting, held in Singapore from 28 September to 2 October 2026. The meeting was hosted by the International Institute of Humanitarian Law, the International Committee of the Red Cross, and the Norwegian Red Cross Society.

Published in 1994, the San Remo Manual consolidates rules of customary international law applicable to armed conflicts at sea, alongside relevant provisions of the 1949 Geneva Conventions and Additional Protocol I of 1977. The update project was launched in 2024 to reflect subsequent legal and operational developments, including changes in State practice and opinio juris, as well as the evolution of naval operations in contemporary armed conflicts.

The Singapore meeting was the second meeting of the Group of Experts, following the first meeting in San Remo in 2025. Participants reviewed more than 60 draft rules proposed by the Drafting Committee and discussed two Option Papers and three Deep Dive Papers. Topics included the basic rules governing the conduct of hostilities, the use of force against merchant vessels and civil aircraft, methods and means of naval warfare, safety measures concerning merchant vessels, jus ad bellum, due regard, critical underwater infrastructure, and the marine environment.

Dr Sun presented a Deep Dive Paper entitled “Protecting the Marine Environment under International Law during Armed Conflict at Sea”. Her presentation examined scientific evidence of the environmental effects of naval operations and the development of international law governing environmental protection in peacetime and during armed conflict. She also identified gaps in the protection of the marine environment during armed conflict at sea and explored possible updates to the Manual’s environmental rules.