The leading post-World War I naval powers of Britain, France, Italy, Japan and the United States concluded a landmark agreement that was intended to slow the burdensome arms race and, it was hoped, reduce the possibilities for future wars. The Agreement was called Five-Power Treaty. The Five-Power Treaty continued to be observed into the 1930s, but then an increasingly militant Japan demanded parity with the U.S. and Britain. That request was denied and Japan in 1934 gave notice that it would withdraw from the treaty in two years — and did so. Five-Power Treaty is also known as the Washington Naval Treaty.