After 1930, most naval powers concentrated on building light cruisers since they had already built up to the maximum limitations for heavy cruisers allowed under the Washington treaty. Japan laid down its four s between 1931 and 1934. The political climate from 1936 to 1939 gave the renewed building of light cruisers an added urgency. The British built 11 during this period, which culminated in the two ships, armed with 12 guns. The new ships were larger and better armored than other British treaty cruisers, with a belt in the Towns and were capable of 32.5 knots, but for the most part tried to stay within past treaty limitations. The US also attempted to follow treaty limitations as it completed seven of its nine s between 1938 and September 1939. These ships were an answer to Japan's "Mogami"s and were an indication of rising tensions in the Pacific theater. Japan, now considering itself under no restrictions, began rearming its "Mogami"s with 10 guns.