The U.S. Defense Department has reiterated its demand that North Korea cancel its planned launch of a long-range missile following Pyongyang's announcement that it has begun preparing for the launch.

Pentagon spokesman John Kirby told reporters Saturday that the launch is an absolute violation of North Korea’s international responsibilities, and it should abide by its promise to the international community by not launching the rocket.

Kirby said the U.S. is in close discussions with South Korea and Japan over the issue.

Critics argue that North Korea’s plan to launch the rocket to put an observation satellite into orbit may be a disguise to test-launch a ballistic long-range missile.