Soviet legal scholar and diplomat who played a major role in formulating Soviet foreign policy as a key adviser to Soviet leaders Nikita Khrushchev (Khrushchev, Nikita Sergeyevich) and Mikhail Gorbachev (Gorbachev, Mikhail).

Tunkin graduated from the Moscow Law Institute in 1935 and received a doctorate from Moscow State University in 1938. He began his diplomatic career in 1939, with postings in such countries as Canada and Korea. From 1952 to 1965 he was head of the Treaties and Legal Division of the Soviet foreign ministry and was involved in both treaty drafting and treaty negotiation. He also taught law at Moscow State University during this period. Tunkin exerted considerable influence in the de-Stalinization movement that prevailed until Khrushchev's political demise in 1964, and he is credited with initiating the theory of peaceful coexistence between the Soviets and the West.

Specializing in maritime and Antarctic law, Tunkin participated in several significant international law conferences. His published works include Foundations of Modern International Law (1956), Problems of the Theory of International Law (1962), Ideological Struggle and International Law (1967), Theory of International Law (1970), and International Law in the International System (1975). Tunkin also served as a delegate to the United Nations General Assembly. From 1964 to 1988 he was the head of the department of international law at Moscow State University.