What is pacta sunt servanda means?

known by the Latin formula pacta sunt servanda (“agreements must be kept”) is arguably the oldest principle of international law. Without such a rule, no international agreement would be binding or enforceable.

Who said pacta sunt servanda?

14. Dr Patrick Healy taught medieval history at Trinity College Dublin and Oxford University and holds a law degree from the University of Toronto. Image: Hugo Grotius, the celebrated seventeenth century jurist and theoretician of natural law who popularized the phrase Pacta Sunt Servanda.