Japan's growing influence over the Pacific and East Asia alarmed the U.S. government, which sought to protect its own colonial (i.e., "sphere of influence") interests in the region, specifically the Philippines and Guam. The United States was able to force an unfavorable naval ratio on Japanese warships at the Washington Conference. The "Five-Power Treaty" stipulated that the Japanese fleet could not grow larger than three-fifths the size of the American and British navies.