Antonios Tzanakopoulos

DPhil (Oxf), LLM (NYU) LLM LLB (Athens)

Antonios is Professor of Public International Law at the Faculty of Law of the University of Oxford and Fellow in Law at St Anne's College. He has taught as a visitor at the Universities of Paris (Paris II–Assas, Paris X–Nanterre), Angers, London (KCL), Athens, Bern (World Trade Institute), Jerusalem (Hebrew University), and Beijing (CUPL). He was previously lecturer in international law at UCL and at the University of Glasgow. Antonios has also delivered a special course at the Xiamen Academy of International Law in 2017 and has been invited by the Curatorium of The Hague Academy of International Law to deliver a special course in 2026. 

Antonios studied law in Athens, New York, and Oxford. He is a general international lawyer and has published in a number of areas reflecting his varied research interests. His books include Disobeying the Security Council (OUP 2011, re-issued in paperback with a new introduction 2013); The Settlement of International Disputes (Hart 2012, co-edited with CJ Tams, 2d ed 2022); The UN Convention on Jurisdictional Immunities of States and their Property (OUP 2013, co-edited with R O'Keefe and CJ Tams); the Research Handbook on the Law of Treaties (Elgar 2014, co-edited with CJ Tams and A Zimmermann, re-issued in paperback 2016); and The Engagement of Domestic Courts with International Law (OUP 2024, co-edited with A Nollkaemper and Y Shany). He has also published in the fields of the law of state responsibility, the law of the sea, international investment law, and others. 

Antonios advises states, international organizations, and other actors on matters of public international law from Three Stone Chambers in Lincoln's Inn. He has acted as counsel and advocate, and has provided expert opinions in a number of cases before international and domestic courts and tribunals, including the International Court of Justice, the International Tribunal for the Law of the Sea, EU courts, the European Court of Human Rights, ad hoc and ICSID arbitral tribunals, and the courts of England and Wales. Some of his recent ICJ and ITLOS cases include acting as counsel for the Republic of Cyprus in the Chagos Advisory Opinion and as counsel and advocate in the Article 63 intervention in Ukraine v Russia, as counsel for Malaysia in the two Advisory Opinions relating to the Occupied Palestinian Territory, as counsel and advocate for Germany in Nicaragua v Germany, and as counsel for Equatorial Guinea in The M/T 'Heroic Idun' (No 2). Antonios also provides training in international law to domestic judges, as well as diplomats, military officers, and other government officials, including on behalf of the United Nations.  

Antonios is the Secretary-General of the International Law Association and the Joint Secretary of its British Branch; and member of the editorial board of Oxford Reports on International Law in Domestic Courts. He served as the Co-Rapporteur of the ILA Study Group on Principles of Engagement of Domestic Courts with International Law (2011-2016), and was contributing editor of EJIL: Talk! (the blog of the European Journal of International Law) 2014-2016. 

Some of his public lectures can be found online; video-lectures for the United Nations Audiovisual Library of International Law, the Hellenic Society of International Law (in Greek), and the Université Grenoble II (in French) are available here (UN / EN), here (GR), and here (FR).