South Korea and Japan agreed to directly share military information such as satellite tracking of North Korea’s missiles. Photo: Getty Images

South Korea and Japan have agreed to directly share military information such as satellite tracking of North Korea’s missiles, reflecting increasing concerns about the threat from Pyongyang’s accelerating weapons program.

The pact, signed in Seoul on Wednesday, removes the need for the U.S. to be a go-between with intelligence from its allies, who have struggled to build cooperative ties due to lingering legacies of Japan’s colonization of the Korean Peninsula from 1910 to 1945.