Which agreement is considered to have laid the foundations for the UN?

The Atlantic Charter

The Atlantic Charter, signed in August 1941 by Franklin D. Roosevelt and Winston Churchill, well before the official entry of the United States into World War II, established guiding principles for the post-war world. This joint declaration outlined the Allies' objectives for the war and the post-war period, focusing on peace, security, and the self-determination of peoples. The spirit and principles of the Atlantic Charter greatly influenced the creation of the United Nations in 1945, aiming to promote international peace and prevent future conflicts. It is seen as a cornerstone in establishing a new world order based on cooperation and dialogue between nations.