The Kellogg–Briand Pact or Pact of Paris – officially the General Treaty for Renunciation of War as an Instrument of National Policy – is a 1928 international agreement on peace in which signatory states promised not to use war to resolve "disputes or conflicts of whatever nature or of whatever origin they may be, which may arise among them". The pact was signed by Germany, France, and the United States on 27 August 1928, and by most other states soon after. Sponsored by France and the U.S., the Pact is named after its authors, United States Secretary of State Frank B. Kellogg and French foreign minister Aristide Briand. The pact was concluded outside the League of Nations and remains in effect.

A common criticism is that the Kellogg–Briand Pact did not live up to all of its aims but has arguably had some success. It was unable to prevent the Second World War but was the base for trial and execution of Nazi leaders in 1946. Furthermore, declared wars became very rare after 1945. It has been ridiculed for its moralism, legalism, and lack of influence on foreign policy. The pact had no mechanism for enforcement, and many historians and political scientists see it as mostly irrelevant and ineffective. Nevertheless, the pact served as the legal basis for the concept of a crime against peace, for which the Nuremberg Tribunal and Tokyo Tribunal tried and executed the top leaders responsible for starting World War II.

Similar provisions to those in the Kellogg–Briand Pact were later incorporated into the Charter of the United Nations and other treaties, which gave rise to a more activist American foreign policy which began with the signing of the pact.